Merge pull request #27796 from yuwata/memstream-util

util: introduce memstream-util

src/analyze/analyze-security.c

@@ -2229,7 +2229,7 @@ static int property_read_ip_filters(
                 void *userdata) {
 
         SecurityInfo *info = userdata;
-        _cleanup_(strv_freep) char **l = NULL;
+        _cleanup_strv_free_ char **l = NULL;
         int r;
 
         assert(bus);

src/basic/memstream-util.c

@@ -0,0 +1,75 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include "alloc-util.h"
+#include "fd-util.h"
+#include "fileio.h"
+#include "log.h"
+#include "memstream-util.h"
+
+void memstream_done(MemStream *m) {
+        assert(m);
+
+        /* First, close file stream, as the buffer may be reallocated on close. */
+        safe_fclose(m->f);
+
+        /* Then, free buffer. */
+        free(m->buf);
+}
+
+FILE* memstream_init(MemStream *m) {
+        assert(m);
+        assert(!m->f);
+
+        m->f = open_memstream_unlocked(&m->buf, &m->sz);
+        return m->f;
+}
+
+int memstream_finalize(MemStream *m, char **ret_buf, size_t *ret_size) {
+        int r;
+
+        assert(m);
+        assert(m->f);
+        assert(ret_buf);
+
+        /* Add terminating NUL, so that the output buffer is a valid string. */
+        fputc('\0', m->f);
+
+        r = fflush_and_check(m->f);
+        if (r < 0)
+                return r;
+
+        m->f = safe_fclose(m->f);
+
+        /* On fclose(), the buffer may be reallocated, and may trigger OOM. */
+        if (!m->buf)
+                return -ENOMEM;
+
+        assert(m->sz > 0);
+
+        *ret_buf = TAKE_PTR(m->buf);
+        if (ret_size)
+                *ret_size = m->sz - 1;
+
+        m->sz = 0; /* For safety when the MemStream object will be reused later. */
+        return 0;
+}
+
+int memstream_dump_internal(
+                int level,
+                int error,
+                const char *file,
+                int line,
+                const char *func,
+                MemStream *m) {
+
+        _cleanup_free_ char *buf = NULL;
+        int r;
+
+        assert(m);
+
+        r = memstream_finalize(m, &buf, NULL);
+        if (r < 0)
+                return log_full_errno(level, r, "Failed to flush memstream: %m: %m");
+
+        return log_dump_internal(level, error, file, line, func, buf);
+}

src/basic/memstream-util.h

@@ -0,0 +1,27 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+#pragma once
+
+#include <stdio.h>
+
+#include "macro.h"
+
+typedef struct MemStream {
+        FILE *f;
+        char *buf;
+        size_t sz;
+} MemStream;
+
+void memstream_done(MemStream *m);
+FILE* memstream_init(MemStream *m);
+int memstream_finalize(MemStream *m, char **ret_buf, size_t *ret_size);
+
+/* This finalizes the passed memstream. */
+int memstream_dump_internal(
+                int level,
+                int error,
+                const char *file,
+                int line,
+                const char *func,
+                MemStream *m);
+#define memstream_dump(level, m)                                        \
+        memstream_dump_internal(level, 0, PROJECT_FILE, __LINE__, __func__, m)

src/basic/meson.build

@@ -53,6 +53,7 @@ basic_sources = files(
         'memfd-util.c',
         'memory-util.c',
         'mempool.c',
+        'memstream-util.c',
         'mkdir.c',
         'mountpoint-util.c',
         'namespace-util.c',

src/basic/string-util.c

@@ -15,6 +15,7 @@
 #include "locale-util.h"
 #include "macro.h"
 #include "memory-util.h"
+#include "memstream-util.h"
 #include "string-util.h"
 #include "strv.h"
 #include "terminal-util.h"
@@ -604,9 +605,9 @@ char *strip_tab_ansi(char **ibuf, size_t *_isz, size_t highlight[2]) {
                 STATE_CSI,
                 STATE_CSO,
         } state = STATE_OTHER;
-        _cleanup_free_ char *obuf = NULL;
-        _cleanup_fclose_ FILE *f = NULL;
-        size_t osz = 0, isz, shift[2] = {}, n_carriage_returns = 0;
+        _cleanup_(memstream_done) MemStream m = {};
+        size_t isz, shift[2] = {}, n_carriage_returns = 0;
+        FILE *f;
 
         assert(ibuf);
         assert(*ibuf);
@@ -629,7 +630,7 @@ char *strip_tab_ansi(char **ibuf, size_t *_isz, size_t highlight[2]) {
 
         /* Note we turn off internal locking on f for performance reasons. It's safe to do so since we
          * created f here and it doesn't leave our scope. */
-        f = open_memstream_unlocked(&obuf, &osz);
+        f = memstream_init(&m);
         if (!f)
                 return NULL;
 
@@ -714,19 +715,12 @@ char *strip_tab_ansi(char **ibuf, size_t *_isz, size_t highlight[2]) {
                 }
         }
 
-        if (fflush_and_check(f) < 0)
-                return NULL;
-
-        f = safe_fclose(f);
-
-        if (!obuf)
+        char *obuf;
+        if (memstream_finalize(&m, &obuf, _isz) < 0)
                 return NULL;
 
         free_and_replace(*ibuf, obuf);
 
-        if (_isz)
-                *_isz = osz;
-
         if (highlight) {
                 highlight[0] += shift[0];
                 highlight[1] += shift[1];

src/boot/measure.c

@@ -11,6 +11,7 @@
 #include "hexdecoct.h"
 #include "json.h"
 #include "main-func.h"
+#include "memstream-util.h"
 #include "openssl-util.h"
 #include "parse-argument.h"
 #include "parse-util.h"
@@ -779,13 +780,12 @@ static int verb_sign(int argc, char *argv[], void *userdata) {
                 if (!pubkey)
                         return log_error_errno(SYNTHETIC_ERRNO(EIO), "Failed to parse public key '%s'.", arg_public_key);
         } else {
-                _cleanup_free_ char *data = NULL;
-                _cleanup_fclose_ FILE *tf = NULL;
-                size_t sz;
+                _cleanup_(memstream_done) MemStream m = {};
+                FILE *tf;
 
                 /* No public key was specified, let's derive it automatically, if we can */
 
-                tf = open_memstream_unlocked(&data, &sz);
+                tf = memstream_init(&m);
                 if (!tf)
                         return log_oom();
 

src/busctl/busctl.c

@@ -21,6 +21,7 @@
 #include "json.h"
 #include "log.h"
 #include "main-func.h"
+#include "memstream-util.h"
 #include "os-util.h"
 #include "pager.h"
 #include "parse-argument.h"
@@ -1035,12 +1036,12 @@ static int introspect(int argc, char **argv, void *userdata) {
                         return bus_log_parse_error(r);
 
                 for (;;) {
-                        _cleanup_fclose_ FILE *mf = NULL;
+                        _cleanup_(memstream_done) MemStream ms = {};
                         _cleanup_free_ char *buf = NULL;
                         const char *name, *contents;
-                        size_t sz = 0;
                         Member *z;
                         char type;
+                        FILE *mf;
 
                         r = sd_bus_message_enter_container(reply, 'e', "sv");
                         if (r < 0)
@@ -1062,7 +1063,7 @@ static int introspect(int argc, char **argv, void *userdata) {
                         if (r < 0)
                                 return bus_log_parse_error(r);
 
-                        mf = open_memstream_unlocked(&buf, &sz);
+                        mf = memstream_init(&ms);
                         if (!mf)
                                 return log_oom();
 
@@ -1070,10 +1071,9 @@ static int introspect(int argc, char **argv, void *userdata) {
                         if (r < 0)
                                 return bus_log_parse_error(r);
 
-                        mf = safe_fclose(mf);
-
-                        if (!buf)
-                                return bus_log_parse_error(ENOMEM);
+                        r = memstream_finalize(&ms, &buf, NULL);
+                        if (r < 0)
+                                return log_error_errno(r, "Failed to flush and close memstream: %m");
 
                         z = set_get(members, &((Member) {
                                                 .type = "property",

src/core/dbus-cgroup.c

@@ -18,6 +18,7 @@
 #include "in-addr-prefix-util.h"
 #include "ip-protocol-list.h"
 #include "limits-util.h"
+#include "memstream-util.h"
 #include "parse-util.h"
 #include "path-util.h"
 #include "percent-util.h"
@@ -657,15 +658,16 @@ static int bus_cgroup_set_transient_property(
                         return r;
 
                 if (!UNIT_WRITE_FLAGS_NOOP(flags)) {
+                        _cleanup_(memstream_done) MemStream m = {};
                         _cleanup_free_ char *buf = NULL;
-                        _cleanup_fclose_ FILE *f = NULL;
-                        size_t size = 0;
+                        FILE *f;
 
                         if (n == 0)
                                 *filters = strv_free(*filters);
 
                         unit_invalidate_cgroup_bpf(u);
-                        f = open_memstream_unlocked(&buf, &size);
+
+                        f = memstream_init(&m);
                         if (!f)
                                 return -ENOMEM;
 
@@ -675,7 +677,7 @@ static int bus_cgroup_set_transient_property(
                         STRV_FOREACH(entry, *filters)
                                 fprintf(f, "%s=%s\n", name, *entry);
 
-                        r = fflush_and_check(f);
+                        r = memstream_finalize(&m, &buf, NULL);
                         if (r < 0)
                                 return r;
 
@@ -736,15 +738,15 @@ static int bus_cgroup_set_transient_property(
                         return r;
 
                 if (!UNIT_WRITE_FLAGS_NOOP(flags)) {
+                        _cleanup_(memstream_done) MemStream m = {};
                         _cleanup_free_ char *buf = NULL;
-                        _cleanup_fclose_ FILE *f = NULL;
-                        size_t size = 0;
+                        FILE *f;
 
                         if (n == 0)
                                 while (c->bpf_foreign_programs)
                                         cgroup_context_remove_bpf_foreign_program(c, c->bpf_foreign_programs);
 
-                        f = open_memstream_unlocked(&buf, &size);
+                        f = memstream_init(&m);
                         if (!f)
                                 return -ENOMEM;
 
@@ -756,7 +758,7 @@ static int bus_cgroup_set_transient_property(
                                                 bpf_cgroup_attach_type_to_string(fp->attach_type),
                                                 fp->bpffs_path);
 
-                        r = fflush_and_check(f);
+                        r = memstream_finalize(&m, &buf, NULL);
                         if (r < 0)
                                 return r;
 
@@ -1403,9 +1405,9 @@ int bus_cgroup_set_property(
                         return r;
 
                 if (!UNIT_WRITE_FLAGS_NOOP(flags)) {
+                        _cleanup_(memstream_done) MemStream m = {};
                         _cleanup_free_ char *buf = NULL;
-                        _cleanup_fclose_ FILE *f = NULL;
-                        size_t size = 0;
+                        FILE *f;
 
                         if (n == 0)
                                 LIST_FOREACH(device_limits, a, c->io_device_limits)
@@ -1413,7 +1415,7 @@ int bus_cgroup_set_property(
 
                         unit_invalidate_cgroup(u, CGROUP_MASK_IO);
 
-                        f = open_memstream_unlocked(&buf, &size);
+                        f = memstream_init(&m);
                         if (!f)
                                 return -ENOMEM;
 
@@ -1422,9 +1424,10 @@ int bus_cgroup_set_property(
                                 if (a->limits[iol_type] != cgroup_io_limit_defaults[iol_type])
                                         fprintf(f, "%s=%s %" PRIu64 "\n", name, a->path, a->limits[iol_type]);
 
-                        r = fflush_and_check(f);
+                        r = memstream_finalize(&m, &buf, NULL);
                         if (r < 0)
                                 return r;
+
                         unit_write_setting(u, flags, name, buf);
                 }
 
@@ -1480,9 +1483,9 @@ int bus_cgroup_set_property(
                         return r;
 
                 if (!UNIT_WRITE_FLAGS_NOOP(flags)) {
+                        _cleanup_(memstream_done) MemStream m = {};
                         _cleanup_free_ char *buf = NULL;
-                        _cleanup_fclose_ FILE *f = NULL;
-                        size_t size = 0;
+                        FILE *f;
 
                         if (n == 0)
                                 while (c->io_device_weights)
@@ -1490,7 +1493,7 @@ int bus_cgroup_set_property(
 
                         unit_invalidate_cgroup(u, CGROUP_MASK_IO);
 
-                        f = open_memstream_unlocked(&buf, &size);
+                        f = memstream_init(&m);
                         if (!f)
                                 return -ENOMEM;
 
@@ -1498,9 +1501,10 @@ int bus_cgroup_set_property(
                         LIST_FOREACH(device_weights, a, c->io_device_weights)
                                 fprintf(f, "IODeviceWeight=%s %" PRIu64 "\n", a->path, a->weight);
 
-                        r = fflush_and_check(f);
+                        r = memstream_finalize(&m, &buf, NULL);
                         if (r < 0)
                                 return r;
+
                         unit_write_setting(u, flags, name, buf);
                 }
 
@@ -1553,9 +1557,9 @@ int bus_cgroup_set_property(
                         return r;
 
                 if (!UNIT_WRITE_FLAGS_NOOP(flags)) {
+                        _cleanup_(memstream_done) MemStream m = {};
                         _cleanup_free_ char *buf = NULL;
-                        _cleanup_fclose_ FILE *f = NULL;
-                        size_t size = 0;
+                        FILE *f;
 
                         if (n == 0)
                                 while (c->io_device_latencies)
@@ -1563,7 +1567,7 @@ int bus_cgroup_set_property(
 
                         unit_invalidate_cgroup(u, CGROUP_MASK_IO);
 
-                        f = open_memstream_unlocked(&buf, &size);
+                        f = memstream_init(&m);
                         if (!f)
                                 return -ENOMEM;
 
@@ -1572,9 +1576,10 @@ int bus_cgroup_set_property(
                                 fprintf(f, "IODeviceLatencyTargetSec=%s %s\n",
                                         a->path, FORMAT_TIMESPAN(a->target_usec, 1));
 
-                        r = fflush_and_check(f);
+                        r = memstream_finalize(&m, &buf, NULL);
                         if (r < 0)
                                 return r;
+
                         unit_write_setting(u, flags, name, buf);
                 }
 
@@ -1638,9 +1643,9 @@ int bus_cgroup_set_property(
                         return r;
 
                 if (!UNIT_WRITE_FLAGS_NOOP(flags)) {
+                        _cleanup_(memstream_done) MemStream m = {};
                         _cleanup_free_ char *buf = NULL;
-                        _cleanup_fclose_ FILE *f = NULL;
-                        size_t size = 0;
+                        FILE *f;
 
                         if (n == 0)
                                 LIST_FOREACH(device_bandwidths, a, c->blockio_device_bandwidths) {
@@ -1652,7 +1657,7 @@ int bus_cgroup_set_property(
 
                         unit_invalidate_cgroup(u, CGROUP_MASK_BLKIO);
 
-                        f = open_memstream_unlocked(&buf, &size);
+                        f = memstream_init(&m);
                         if (!f)
                                 return -ENOMEM;
 
@@ -1668,7 +1673,7 @@ int bus_cgroup_set_property(
                                                 fprintf(f, "BlockIOWriteBandwidth=%s %" PRIu64 "\n", a->path, a->wbps);
                         }
 
-                        r = fflush_and_check(f);
+                        r = memstream_finalize(&m, &buf, NULL);
                         if (r < 0)
                                 return r;
 
@@ -1727,9 +1732,9 @@ int bus_cgroup_set_property(
                         return r;
 
                 if (!UNIT_WRITE_FLAGS_NOOP(flags)) {
+                        _cleanup_(memstream_done) MemStream m = {};
                         _cleanup_free_ char *buf = NULL;
-                        _cleanup_fclose_ FILE *f = NULL;
-                        size_t size = 0;
+                        FILE *f;
 
                         if (n == 0)
                                 while (c->blockio_device_weights)
@@ -1737,7 +1742,7 @@ int bus_cgroup_set_property(
 
                         unit_invalidate_cgroup(u, CGROUP_MASK_BLKIO);
 
-                        f = open_memstream_unlocked(&buf, &size);
+                        f = memstream_init(&m);
                         if (!f)
                                 return -ENOMEM;
 
@@ -1745,7 +1750,7 @@ int bus_cgroup_set_property(
                         LIST_FOREACH(device_weights, a, c->blockio_device_weights)
                                 fprintf(f, "BlockIODeviceWeight=%s %" PRIu64 "\n", a->path, a->weight);
 
-                        r = fflush_and_check(f);
+                        r = memstream_finalize(&m, &buf, NULL);
                         if (r < 0)
                                 return r;
 
@@ -1830,9 +1835,9 @@ int bus_cgroup_set_property(
                         return r;
 
                 if (!UNIT_WRITE_FLAGS_NOOP(flags)) {
+                        _cleanup_(memstream_done) MemStream m = {};
                         _cleanup_free_ char *buf = NULL;
-                        _cleanup_fclose_ FILE *f = NULL;
-                        size_t size = 0;
+                        FILE *f;
 
                         if (n == 0)
                                 while (c->device_allow)
@@ -1840,7 +1845,7 @@ int bus_cgroup_set_property(
 
                         unit_invalidate_cgroup(u, CGROUP_MASK_DEVICES);
 
-                        f = open_memstream_unlocked(&buf, &size);
+                        f = memstream_init(&m);
                         if (!f)
                                 return -ENOMEM;
 
@@ -1848,9 +1853,10 @@ int bus_cgroup_set_property(
                         LIST_FOREACH(device_allow, a, c->device_allow)
                                 fprintf(f, "DeviceAllow=%s %s%s%s\n", a->path, a->r ? "r" : "", a->w ? "w" : "", a->m ? "m" : "");
 
-                        r = fflush_and_check(f);
+                        r = memstream_finalize(&m, &buf, NULL);
                         if (r < 0)
                                 return r;
+
                         unit_write_setting(u, flags, name, buf);
                 }
 
@@ -1939,14 +1945,15 @@ int bus_cgroup_set_property(
                         return r;
 
                 if (!UNIT_WRITE_FLAGS_NOOP(flags)) {
+                        _cleanup_(memstream_done) MemStream m = {};
                         _cleanup_free_ char *buf = NULL;
-                        _cleanup_fclose_ FILE *f = NULL;
-                        size_t size = 0;
                         Set **prefixes;
                         bool *reduced;
+                        FILE *f;
 
                         unit_invalidate_cgroup_bpf(u);
-                        f = open_memstream_unlocked(&buf, &size);
+
+                        f = memstream_init(&m);
                         if (!f)
                                 return -ENOMEM;
 
@@ -1971,7 +1978,7 @@ int bus_cgroup_set_property(
                                                 IN_ADDR_PREFIX_TO_STRING(p->family, &p->address, p->prefixlen));
                         }
 
-                        r = fflush_and_check(f);
+                        r = memstream_finalize(&m, &buf, NULL);
                         if (r < 0)
                                 return r;
 
@@ -2100,9 +2107,9 @@ int bus_cgroup_set_property(
                         return r;
 
                 if (!UNIT_WRITE_FLAGS_NOOP(flags)) {
+                        _cleanup_(memstream_done) MemStream m = {};
                         _cleanup_free_ char *buf = NULL;
-                        _cleanup_fclose_ FILE *f = NULL;
-                        size_t size = 0;
+                        FILE *f;
 
                         if (n == 0)
                                 cgroup_context_remove_socket_bind(list);
@@ -2114,18 +2121,20 @@ int bus_cgroup_set_property(
                                                  "Starting this unit will fail!", u->id);
                         }
 
-                        f = open_memstream_unlocked(&buf, &size);
+                        f = memstream_init(&m);
                         if (!f)
                                 return -ENOMEM;
 
-                        fprintf(f, "%s:", name);
+                        if (n == 0)
+                                fprintf(f, "%s=\n", name);
+                        else
+                                LIST_FOREACH(socket_bind_items, item, *list) {
+                                        fprintf(f, "%s=", name);
+                                        cgroup_context_dump_socket_bind_item(item, f);
+                                        fputc('\n', f);
+                                }
 
-                        LIST_FOREACH(socket_bind_items, item, *list)
-                                cgroup_context_dump_socket_bind_item(item, f);
-
-                        fputc('\n', f);
-
-                        r = fflush_and_check(f);
+                        r = memstream_finalize(&m, &buf, NULL);
                         if (r < 0)
                                 return r;
 

src/core/dbus-execute.c

@@ -26,6 +26,7 @@
 #include "io-util.h"
 #include "ioprio-util.h"
 #include "journal-file.h"
+#include "memstream-util.h"
 #include "missing_ioprio.h"
 #include "mountpoint-util.h"
 #include "namespace.h"
@@ -1616,14 +1617,14 @@ int bus_set_transient_exec_command(
                 return r;
 
         if (!UNIT_WRITE_FLAGS_NOOP(flags)) {
+                _cleanup_(memstream_done) MemStream m = {};
                 _cleanup_free_ char *buf = NULL;
-                _cleanup_fclose_ FILE *f = NULL;
-                size_t size = 0;
+                FILE *f;
 
                 if (n == 0)
                         *exec_command = exec_command_free_list(*exec_command);
 
-                f = open_memstream_unlocked(&buf, &size);
+                f = memstream_init(&m);
                 if (!f)
                         return -ENOMEM;
 
@@ -1656,7 +1657,7 @@ int bus_set_transient_exec_command(
                         }
                 }
 
-                r = fflush_and_check(f);
+                r = memstream_finalize(&m, &buf, NULL);
                 if (r < 0)
                         return r;
 
@@ -3220,17 +3221,16 @@ int bus_exec_context_set_transient_property(
                 return 1;
 
         } else if (streq(name, "EnvironmentFiles")) {
-
+                _cleanup_(memstream_done) MemStream m = {};
                 _cleanup_free_ char *joined = NULL;
-                _cleanup_fclose_ FILE *f = NULL;
                 _cleanup_strv_free_ char **l = NULL;
-                size_t size = 0;
+                FILE *f;
 
                 r = sd_bus_message_enter_container(message, 'a', "(sb)");
                 if (r < 0)
                         return r;
 
-                f = open_memstream_unlocked(&joined, &size);
+                f = memstream_init(&m);
                 if (!f)
                         return -ENOMEM;
 
@@ -3286,7 +3286,7 @@ int bus_exec_context_set_transient_property(
                 if (r < 0)
                         return r;
 
-                r = fflush_and_check(f);
+                r = memstream_finalize(&m, &joined, NULL);
                 if (r < 0)
                         return r;
 

src/core/dbus-manager.c

@@ -2153,7 +2153,7 @@ static int list_unit_files_by_patterns(sd_bus_message *message, void *userdata,
         _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
         Manager *m = ASSERT_PTR(userdata);
         UnitFileList *item;
-        _cleanup_(hashmap_freep) Hashmap *h = NULL;
+        _cleanup_hashmap_free_ Hashmap *h = NULL;
         int r;
 
         assert(message);

src/core/fuzz-unit-file.c

@@ -6,14 +6,13 @@
 #include "install.h"
 #include "load-fragment.h"
 #include "manager-dump.h"
+#include "memstream-util.h"
 #include "string-util.h"
 #include "unit-serialize.h"
 #include "utf8.h"
 
 int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
-        _cleanup_free_ char *out = NULL; /* out should be freed after g */
-        size_t out_size;
-        _cleanup_fclose_ FILE *f = NULL, *g = NULL;
+        _cleanup_fclose_ FILE *f = NULL;
         _cleanup_free_ char *p = NULL;
         UnitType t;
         _cleanup_(manager_freep) Manager *m = NULL;
@@ -79,9 +78,10 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
                         u,
                         NULL);
 
-        g = open_memstream_unlocked(&out, &out_size);
-        assert_se(g);
+        _cleanup_(memstream_done) MemStream ms = {};
+        FILE *g;
 
+        assert_se(g = memstream_init(&ms));
         unit_dump(u, g, "");
         manager_dump(m, g, /* patterns= */ NULL, ">>>");
 

src/core/manager-dump.c

@@ -5,6 +5,7 @@
 #include "fileio.h"
 #include "hashmap.h"
 #include "manager-dump.h"
+#include "memstream-util.h"
 #include "unit-serialize.h"
 
 void manager_dump_jobs(Manager *s, FILE *f, char **patterns, const char *prefix) {
@@ -75,32 +76,19 @@ void manager_dump(Manager *m, FILE *f, char **patterns, const char *prefix) {
 }
 
 int manager_get_dump_string(Manager *m, char **patterns, char **ret) {
-        _cleanup_free_ char *dump = NULL;
-        _cleanup_fclose_ FILE *f = NULL;
-        size_t size;
-        int r;
+        _cleanup_(memstream_done) MemStream ms = {};
+        FILE *f;
 
         assert(m);
         assert(ret);
 
-        f = open_memstream_unlocked(&dump, &size);
+        f = memstream_init(&ms);
         if (!f)
                 return -errno;
 
         manager_dump(m, f, patterns, NULL);
 
-        r = fflush_and_check(f);
-        if (r < 0)
-                return r;
-
-        f = safe_fclose(f);
-
-        if (!dump)
-                return -ENOMEM;
-
-        *ret = TAKE_PTR(dump);
-
-        return 0;
+        return memstream_finalize(&ms, ret, NULL);
 }
 
 void manager_test_summary(Manager *m) {

src/core/unit.c

@@ -1082,7 +1082,7 @@ static void unit_merge_dependencies(Unit *u, Unit *other) {
         }
 
         for (;;) {
-                _cleanup_(hashmap_freep) Hashmap *other_deps = NULL;
+                _cleanup_hashmap_free_ Hashmap *other_deps = NULL;
                 UnitDependencyInfo di_back;
                 Unit *back;
 

src/coredump/coredump.c

@@ -36,6 +36,7 @@
 #include "macro.h"
 #include "main-func.h"
 #include "memory-util.h"
+#include "memstream-util.h"
 #include "mkdir-label.h"
 #include "parse-util.h"
 #include "process-util.h"
@@ -641,17 +642,16 @@ static int allocate_journal_field(int fd, size_t size, char **ret, size_t *ret_s
  * flags:  0100002
  * EOF
  */
-static int compose_open_fds(pid_t pid, char **open_fds) {
+static int compose_open_fds(pid_t pid, char **ret) {
+        _cleanup_(memstream_done) MemStream m = {};
         _cleanup_closedir_ DIR *proc_fd_dir = NULL;
         _cleanup_close_ int proc_fdinfo_fd = -EBADF;
-        _cleanup_free_ char *buffer = NULL;
-        _cleanup_fclose_ FILE *stream = NULL;
         const char *fddelim = "", *path;
-        size_t size = 0;
+        FILE *stream;
         int r;
 
         assert(pid >= 0);
-        assert(open_fds != NULL);
+        assert(ret);
 
         path = procfs_file_alloca(pid, "fd");
         proc_fd_dir = opendir(path);
@@ -662,7 +662,7 @@ static int compose_open_fds(pid_t pid, char **open_fds) {
         if (proc_fdinfo_fd < 0)
                 return -errno;
 
-        stream = open_memstream_unlocked(&buffer, &size);
+        stream = memstream_init(&m);
         if (!stream)
                 return -ENOMEM;
 
@@ -701,18 +701,7 @@ static int compose_open_fds(pid_t pid, char **open_fds) {
                 }
         }
 
-        errno = 0;
-        stream = safe_fclose(stream);
-
-        if (errno > 0)
-                return -errno;
-
-        if (!buffer)
-                return -ENOMEM;
-
-        *open_fds = TAKE_PTR(buffer);
-
-        return 0;
+        return memstream_finalize(&m, ret, NULL);
 }
 
 static int get_process_ns(pid_t pid, const char *namespace, ino_t *ns) {

src/creds/creds.c

@@ -122,7 +122,7 @@ not_found:
 }
 
 static int add_credentials_to_table(Table *t, bool encrypted) {
-        _cleanup_(closedirp) DIR *d = NULL;
+        _cleanup_closedir_ DIR *d = NULL;
         const char *prefix;
         int r;
 
@@ -382,7 +382,7 @@ static int verb_cat(int argc, char **argv, void *userdata) {
 
                 /* Look both in regular and in encrypted credentials */
                 for (encrypted = 0; encrypted < 2; encrypted++) {
-                        _cleanup_(closedirp) DIR *d = NULL;
+                        _cleanup_closedir_ DIR *d = NULL;
 
                         r = open_credential_directory(encrypted, &d, NULL);
                         if (r < 0)

src/cryptenroll/cryptenroll-wipe.c

@@ -88,7 +88,7 @@ static int find_slots_by_mask(
                 Set *keep_slots,
                 unsigned by_mask) {
 
-        _cleanup_(set_freep) Set *listed_slots = NULL;
+        _cleanup_set_free_ Set *listed_slots = NULL;
         int r;
 
         assert(cd);
@@ -301,7 +301,7 @@ int wipe_slots(struct crypt_device *cd,
                unsigned by_mask,
                int except_slot) {
 
-        _cleanup_(set_freep) Set *wipe_slots = NULL, *wipe_tokens = NULL, *keep_slots = NULL;
+        _cleanup_set_free_ Set *wipe_slots = NULL, *wipe_tokens = NULL, *keep_slots = NULL;
         _cleanup_free_ int *ordered_slots = NULL, *ordered_tokens = NULL;
         size_t n_ordered_slots = 0, n_ordered_tokens = 0;
         int r, slot_max, ret;

src/dissect/dissect.c

@@ -1569,7 +1569,7 @@ static int action_with(DissectedImage *m, LoopDevice *d) {
 }
 
 static int action_discover(void) {
-        _cleanup_(hashmap_freep) Hashmap *images = NULL;
+        _cleanup_hashmap_free_ Hashmap *images = NULL;
         _cleanup_(table_unrefp) Table *t = NULL;
         Image *img;
         int r;

src/fuzz/fuzz-json.c

@@ -5,12 +5,13 @@
 #include "fd-util.h"
 #include "fuzz.h"
 #include "json.h"
+#include "memstream-util.h"
 
 int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
-        _cleanup_free_ char *out = NULL; /* out should be freed after g */
-        size_t out_size;
-        _cleanup_fclose_ FILE *f = NULL, *g = NULL;
+        _cleanup_(memstream_done) MemStream m = {};
         _cleanup_(json_variant_unrefp) JsonVariant *v = NULL;
+        _cleanup_fclose_ FILE *f = NULL;
+        FILE *g = NULL;
         int r;
 
         /* Disable most logging if not running standalone */
@@ -27,7 +28,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         }
 
         if (getenv_bool("SYSTEMD_FUZZ_OUTPUT") <= 0)
-                assert_se(g = open_memstream_unlocked(&out, &out_size));
+                assert_se(g = memstream_init(&m));
 
         json_variant_dump(v, 0, g ?: stdout, NULL);
         json_variant_dump(v, JSON_FORMAT_PRETTY|JSON_FORMAT_COLOR|JSON_FORMAT_SOURCE, g ?: stdout, NULL);

src/home/homectl-pkcs11.c

@@ -100,7 +100,7 @@ static int add_pkcs11_token_uri(JsonVariant **v, const char *uri) {
 
 int identity_add_token_pin(JsonVariant **v, const char *pin) {
         _cleanup_(json_variant_unrefp) JsonVariant *w = NULL, *l = NULL;
-        _cleanup_(strv_free_erasep) char **pins = NULL;
+        _cleanup_strv_free_erase_ char **pins = NULL;
         int r;
 
         assert(v);

src/home/homectl-recovery-key.c

@@ -67,7 +67,7 @@ static int add_public(JsonVariant **v) {
 
 static int add_secret(JsonVariant **v, const char *password) {
         _cleanup_(json_variant_unrefp) JsonVariant *w = NULL, *l = NULL;
-        _cleanup_(strv_free_erasep) char **passwords = NULL;
+        _cleanup_strv_free_erase_ char **passwords = NULL;
         int r;
 
         assert(v);

src/home/homectl.c

@@ -210,7 +210,7 @@ static int acquire_existing_password(
                 bool emphasize_current,
                 AskPasswordFlags flags) {
 
-        _cleanup_(strv_free_erasep) char **password = NULL;
+        _cleanup_strv_free_erase_ char **password = NULL;
         _cleanup_(erase_and_freep) char *envpw = NULL;
         _cleanup_free_ char *question = NULL;
         int r;
@@ -271,7 +271,7 @@ static int acquire_recovery_key(
                 UserRecord *hr,
                 AskPasswordFlags flags) {
 
-        _cleanup_(strv_free_erasep) char **recovery_key = NULL;
+        _cleanup_strv_free_erase_ char **recovery_key = NULL;
         _cleanup_(erase_and_freep) char *envpw = NULL;
         _cleanup_free_ char *question = NULL;
         int r;
@@ -329,7 +329,7 @@ static int acquire_token_pin(
                 UserRecord *hr,
                 AskPasswordFlags flags) {
 
-        _cleanup_(strv_free_erasep) char **pin = NULL;
+        _cleanup_strv_free_erase_ char **pin = NULL;
         _cleanup_(erase_and_freep) char *envpin = NULL;
         _cleanup_free_ char *question = NULL;
         int r;
@@ -699,7 +699,7 @@ static char **mangle_user_list(char **list, char ***ret_allocated) {
 
 static int inspect_home(int argc, char *argv[], void *userdata) {
         _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
-        _cleanup_(strv_freep) char **mangled_list = NULL;
+        _cleanup_strv_free_ char **mangled_list = NULL;
         int r, ret = 0;
         char **items;
 
@@ -783,7 +783,7 @@ static int inspect_home(int argc, char *argv[], void *userdata) {
 
 static int authenticate_home(int argc, char *argv[], void *userdata) {
         _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
-        _cleanup_(strv_freep) char **mangled_list = NULL;
+        _cleanup_strv_free_ char **mangled_list = NULL;
         int r, ret = 0;
         char **items;
 
@@ -1187,7 +1187,7 @@ static int acquire_new_password(
                 (void) suggest_passwords();
 
         for (;;) {
-                _cleanup_(strv_free_erasep) char **first = NULL, **second = NULL;
+                _cleanup_strv_free_erase_ char **first = NULL, **second = NULL;
                 _cleanup_free_ char *question = NULL;
 
                 if (--i == 0)
@@ -3162,7 +3162,7 @@ static int parse_argv(int argc, char *argv[]) {
 
                 case ARG_SSH_AUTHORIZED_KEYS: {
                         _cleanup_(json_variant_unrefp) JsonVariant *v = NULL;
-                        _cleanup_(strv_freep) char **l = NULL, **add = NULL;
+                        _cleanup_strv_free_ char **l = NULL, **add = NULL;
 
                         if (isempty(optarg)) {
                                 r = drop_from_identity("sshAuthorizedKeys");

src/home/homed-manager-bus.c

@@ -36,7 +36,7 @@ static int property_get_auto_login(
                 return r;
 
         HASHMAP_FOREACH(h, m->homes_by_name) {
-                _cleanup_(strv_freep) char **seats = NULL;
+                _cleanup_strv_free_ char **seats = NULL;
                 _cleanup_free_ char *home_path = NULL;
 
                 r = home_auto_login(h, &seats);

src/home/homed-manager.c

@@ -1357,7 +1357,7 @@ static int manager_enumerate_devices(Manager *m) {
 }
 
 static int manager_load_key_pair(Manager *m) {
-        _cleanup_(fclosep) FILE *f = NULL;
+        _cleanup_fclose_ FILE *f = NULL;
         struct stat st;
         int r;
 

src/home/homework-cifs.c

@@ -60,7 +60,7 @@ int home_setup_cifs(
         STRV_FOREACH(pw, h->password) {
                 _cleanup_(unlink_and_freep) char *p = NULL;
                 _cleanup_free_ char *options = NULL;
-                _cleanup_(fclosep) FILE *f = NULL;
+                _cleanup_fclose_ FILE *f = NULL;
                 pid_t mount_pid;
                 int exit_status;
 

src/home/homework.c

@@ -511,7 +511,7 @@ int home_sync_and_statfs(int root_fd, struct statfs *ret) {
 }
 
 static int read_identity_file(int root_fd, JsonVariant **ret) {
-        _cleanup_(fclosep) FILE *identity_file = NULL;
+        _cleanup_fclose_ FILE *identity_file = NULL;
         _cleanup_close_ int identity_fd = -EBADF;
         unsigned line, column;
         int r;
@@ -542,7 +542,7 @@ static int read_identity_file(int root_fd, JsonVariant **ret) {
 
 static int write_identity_file(int root_fd, JsonVariant *v, uid_t uid) {
         _cleanup_(json_variant_unrefp) JsonVariant *normalized = NULL;
-        _cleanup_(fclosep) FILE *identity_file = NULL;
+        _cleanup_fclose_ FILE *identity_file = NULL;
         _cleanup_close_ int identity_fd = -EBADF;
         _cleanup_free_ char *fn = NULL;
         int r;
@@ -1088,7 +1088,7 @@ static int user_record_compile_effective_passwords(
                 PasswordCache *cache,
                 char ***ret_effective_passwords) {
 
-        _cleanup_(strv_free_erasep) char **effective = NULL;
+        _cleanup_strv_free_erase_ char **effective = NULL;
         size_t n;
         int r;
 
@@ -1307,7 +1307,7 @@ static int determine_default_storage(UserStorage *ret) {
 }
 
 static int home_create(UserRecord *h, UserRecord **ret_home) {
-        _cleanup_(strv_free_erasep) char **effective_passwords = NULL;
+        _cleanup_strv_free_erase_ char **effective_passwords = NULL;
         _cleanup_(home_setup_done) HomeSetup setup = HOME_SETUP_INIT;
         _cleanup_(user_record_unrefp) UserRecord *new_home = NULL;
         _cleanup_(password_cache_free) PasswordCache cache = {};
@@ -1679,7 +1679,7 @@ static int home_resize(UserRecord *h, bool automatic, UserRecord **ret) {
 
 static int home_passwd(UserRecord *h, UserRecord **ret_home) {
         _cleanup_(user_record_unrefp) UserRecord *header_home = NULL, *embedded_home = NULL, *new_home = NULL;
-        _cleanup_(strv_free_erasep) char **effective_passwords = NULL;
+        _cleanup_strv_free_erase_ char **effective_passwords = NULL;
         _cleanup_(home_setup_done) HomeSetup setup = HOME_SETUP_INIT;
         _cleanup_(password_cache_free) PasswordCache cache = {};
         HomeSetupFlags flags = 0;
@@ -1850,7 +1850,7 @@ static int home_unlock(UserRecord *h) {
 static int run(int argc, char *argv[]) {
         _cleanup_(user_record_unrefp) UserRecord *home = NULL, *new_home = NULL;
         _cleanup_(json_variant_unrefp) JsonVariant *v = NULL;
-        _cleanup_(fclosep) FILE *opened_file = NULL;
+        _cleanup_fclose_ FILE *opened_file = NULL;
         unsigned line = 0, column = 0;
         const char *json_path = NULL;
         FILE *json_file;

src/home/user-record-sign.c

@@ -3,6 +3,7 @@
 #include <openssl/pem.h>
 
 #include "fd-util.h"
+#include "memstream-util.h"
 #include "user-record-sign.h"
 #include "fileio.h"
 
@@ -30,13 +31,14 @@ static int user_record_signable_json(UserRecord *ur, char **ret) {
 DEFINE_TRIVIAL_CLEANUP_FUNC_FULL(EVP_MD_CTX*, EVP_MD_CTX_free, NULL);
 
 int user_record_sign(UserRecord *ur, EVP_PKEY *private_key, UserRecord **ret) {
+        _cleanup_(memstream_done) MemStream m = {};
         _cleanup_(json_variant_unrefp) JsonVariant *encoded = NULL, *v = NULL;
         _cleanup_(user_record_unrefp) UserRecord *signed_ur = NULL;
         _cleanup_(EVP_MD_CTX_freep) EVP_MD_CTX *md_ctx = NULL;
         _cleanup_free_ char *text = NULL, *key = NULL;
-        size_t signature_size = 0, key_size = 0;
         _cleanup_free_ void *signature = NULL;
-        _cleanup_fclose_ FILE *mf = NULL;
+        size_t signature_size = 0;
+        FILE *f;
         int r;
 
         assert(ur);
@@ -65,14 +67,14 @@ int user_record_sign(UserRecord *ur, EVP_PKEY *private_key, UserRecord **ret) {
         if (EVP_DigestSign(md_ctx, signature, &signature_size, (uint8_t*) text, strlen(text)) <= 0)
                 return -EIO;
 
-        mf = open_memstream_unlocked(&key, &key_size);
-        if (!mf)
+        f = memstream_init(&m);
+        if (!f)
                 return -ENOMEM;
 
-        if (PEM_write_PUBKEY(mf, private_key) <= 0)
+        if (PEM_write_PUBKEY(f, private_key) <= 0)
                 return -EIO;
 
-        r = fflush_and_check(mf);
+        r = memstream_finalize(&m, &key, NULL);
         if (r < 0)
                 return r;
 

src/home/user-record-util.c

@@ -871,7 +871,7 @@ int user_record_set_hashed_password(UserRecord *h, char **hashed_password) {
 
 int user_record_set_password(UserRecord *h, char **password, bool prepend) {
         _cleanup_(json_variant_unrefp) JsonVariant *w = NULL;
-        _cleanup_(strv_free_erasep) char **e = NULL;
+        _cleanup_strv_free_erase_ char **e = NULL;
         int r;
 
         assert(h);
@@ -933,7 +933,7 @@ int user_record_set_password(UserRecord *h, char **password, bool prepend) {
 
 int user_record_set_token_pin(UserRecord *h, char **pin, bool prepend) {
         _cleanup_(json_variant_unrefp) JsonVariant *w = NULL;
-        _cleanup_(strv_free_erasep) char **e = NULL;
+        _cleanup_strv_free_erase_ char **e = NULL;
         int r;
 
         assert(h);

src/journal/journalctl.c

@@ -49,6 +49,7 @@
 #include "logs-show.h"
 #include "main-func.h"
 #include "memory-util.h"
+#include "memstream-util.h"
 #include "missing_sched.h"
 #include "mkdir.h"
 #include "mount-util.h"
@@ -1758,15 +1759,14 @@ static int format_journal_url(
                 sd_id128_t machine,
                 bool full,
                 char **ret_url) {
-        _cleanup_free_ char *url = NULL;
-        _cleanup_fclose_ FILE *f = NULL;
-        size_t url_size = 0;
-        int r;
+
+        _cleanup_(memstream_done) MemStream m = {};
+        FILE *f;
 
         assert(seed);
         assert(seed_size > 0);
 
-        f = open_memstream_unlocked(&url, &url_size);
+        f = memstream_init(&m);
         if (!f)
                 return -ENOMEM;
 
@@ -1787,17 +1787,7 @@ static int format_journal_url(
                         fprintf(f, ";hostname=%s", hn);
         }
 
-        r = fflush_and_check(f);
-        if (r < 0)
-                return r;
-
-        f = safe_fclose(f);
-
-        if (!url)
-                return -ENOMEM;
-
-        *ret_url = TAKE_PTR(url);
-        return 0;
+        return memstream_finalize(&m, ret_url, NULL);
 }
 #endif
 

src/libsystemd/sd-bus/bus-introspect.c

@@ -8,6 +8,7 @@
 #include "fd-util.h"
 #include "fileio.h"
 #include "memory-util.h"
+#include "memstream-util.h"
 #include "string-util.h"
 
 #define BUS_INTROSPECT_DOCTYPE                                       \
@@ -68,52 +69,59 @@
         " </interface>\n"
 
 int introspect_begin(struct introspect *i, bool trusted) {
+        FILE *f;
+
         assert(i);
 
         *i = (struct introspect) {
                 .trusted = trusted,
         };
 
-        i->f = open_memstream_unlocked(&i->introspection, &i->size);
-        if (!i->f)
+        f = memstream_init(&i->m);
+        if (!f)
                 return -ENOMEM;
 
         fputs(BUS_INTROSPECT_DOCTYPE
-              "<node>\n", i->f);
+              "<node>\n", f);
 
         return 0;
 }
 
 int introspect_write_default_interfaces(struct introspect *i, bool object_manager) {
         assert(i);
+        assert(i->m.f);
 
         fputs(BUS_INTROSPECT_INTERFACE_PEER
               BUS_INTROSPECT_INTERFACE_INTROSPECTABLE
-              BUS_INTROSPECT_INTERFACE_PROPERTIES, i->f);
+              BUS_INTROSPECT_INTERFACE_PROPERTIES, i->m.f);
 
         if (object_manager)
-                fputs(BUS_INTROSPECT_INTERFACE_OBJECT_MANAGER, i->f);
+                fputs(BUS_INTROSPECT_INTERFACE_OBJECT_MANAGER, i->m.f);
 
         return 0;
 }
 
-static int set_interface_name(struct introspect *intro, const char *interface_name) {
-        if (streq_ptr(intro->interface_name, interface_name))
+static int set_interface_name(struct introspect *i, const char *interface_name) {
+        assert(i);
+        assert(i->m.f);
+
+        if (streq_ptr(i->interface_name, interface_name))
                 return 0;
 
-        if (intro->interface_name)
-                fputs(" </interface>\n", intro->f);
+        if (i->interface_name)
+                fputs(" </interface>\n", i->m.f);
 
         if (interface_name)
-                fprintf(intro->f, " <interface name=\"%s\">\n", interface_name);
+                fprintf(i->m.f, " <interface name=\"%s\">\n", interface_name);
 
-        return free_and_strdup(&intro->interface_name, interface_name);
+        return free_and_strdup(&i->interface_name, interface_name);
 }
 
 int introspect_write_child_nodes(struct introspect *i, OrderedSet *s, const char *prefix) {
         char *node;
 
         assert(i);
+        assert(i->m.f);
         assert(prefix);
 
         assert_se(set_interface_name(i, NULL) >= 0);
@@ -123,7 +131,7 @@ int introspect_write_child_nodes(struct introspect *i, OrderedSet *s, const char
 
                 e = object_path_startswith(node, prefix);
                 if (e && e[0])
-                        fprintf(i->f, " <node name=\"%s\"/>\n", e);
+                        fprintf(i->m.f, " <node name=\"%s\"/>\n", e);
 
                 free(node);
         }
@@ -132,28 +140,31 @@ int introspect_write_child_nodes(struct introspect *i, OrderedSet *s, const char
 }
 
 static void introspect_write_flags(struct introspect *i, int type, uint64_t flags) {
+        assert(i);
+        assert(i->m.f);
+
         if (flags & SD_BUS_VTABLE_DEPRECATED)
-                fputs("   <annotation name=\"org.freedesktop.DBus.Deprecated\" value=\"true\"/>\n", i->f);
+                fputs("   <annotation name=\"org.freedesktop.DBus.Deprecated\" value=\"true\"/>\n", i->m.f);
 
         if (type == _SD_BUS_VTABLE_METHOD && (flags & SD_BUS_VTABLE_METHOD_NO_REPLY))
-                fputs("   <annotation name=\"org.freedesktop.DBus.Method.NoReply\" value=\"true\"/>\n", i->f);
+                fputs("   <annotation name=\"org.freedesktop.DBus.Method.NoReply\" value=\"true\"/>\n", i->m.f);
 
         if (IN_SET(type, _SD_BUS_VTABLE_PROPERTY, _SD_BUS_VTABLE_WRITABLE_PROPERTY)) {
                 if (flags & SD_BUS_VTABLE_PROPERTY_EXPLICIT)
-                        fputs("   <annotation name=\"org.freedesktop.systemd1.Explicit\" value=\"true\"/>\n", i->f);
+                        fputs("   <annotation name=\"org.freedesktop.systemd1.Explicit\" value=\"true\"/>\n", i->m.f);
 
                 if (flags & SD_BUS_VTABLE_PROPERTY_CONST)
-                        fputs("   <annotation name=\"org.freedesktop.DBus.Property.EmitsChangedSignal\" value=\"const\"/>\n", i->f);
+                        fputs("   <annotation name=\"org.freedesktop.DBus.Property.EmitsChangedSignal\" value=\"const\"/>\n", i->m.f);
                 else if (flags & SD_BUS_VTABLE_PROPERTY_EMITS_INVALIDATION)
-                        fputs("   <annotation name=\"org.freedesktop.DBus.Property.EmitsChangedSignal\" value=\"invalidates\"/>\n", i->f);
+                        fputs("   <annotation name=\"org.freedesktop.DBus.Property.EmitsChangedSignal\" value=\"invalidates\"/>\n", i->m.f);
                 else if (!(flags & SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE))
-                        fputs("   <annotation name=\"org.freedesktop.DBus.Property.EmitsChangedSignal\" value=\"false\"/>\n", i->f);
+                        fputs("   <annotation name=\"org.freedesktop.DBus.Property.EmitsChangedSignal\" value=\"false\"/>\n", i->m.f);
         }
 
         if (!i->trusted &&
             IN_SET(type, _SD_BUS_VTABLE_METHOD, _SD_BUS_VTABLE_WRITABLE_PROPERTY) &&
             !(flags & SD_BUS_VTABLE_UNPRIVILEGED))
-                fputs("   <annotation name=\"org.freedesktop.systemd1.Privileged\" value=\"true\"/>\n", i->f);
+                fputs("   <annotation name=\"org.freedesktop.systemd1.Privileged\" value=\"true\"/>\n", i->m.f);
 }
 
 /* Note that "names" is both an input and an output parameter. It initially points to the first argument name in a
@@ -161,6 +172,9 @@ static void introspect_write_flags(struct introspect *i, int type, uint64_t flag
 static int introspect_write_arguments(struct introspect *i, const char *signature, const char **names, const char *direction) {
         int r;
 
+        assert(i);
+        assert(i->m.f);
+
         for (;;) {
                 size_t l;
 
@@ -171,17 +185,17 @@ static int introspect_write_arguments(struct introspect *i, const char *signatur
                 if (r < 0)
                         return r;
 
-                fprintf(i->f, "   <arg type=\"%.*s\"", (int) l, signature);
+                fprintf(i->m.f, "   <arg type=\"%.*s\"", (int) l, signature);
 
                 if (**names != '\0') {
-                        fprintf(i->f, " name=\"%s\"", *names);
+                        fprintf(i->m.f, " name=\"%s\"", *names);
                         *names += strlen(*names) + 1;
                 }
 
                 if (direction)
-                        fprintf(i->f, " direction=\"%s\"/>\n", direction);
+                        fprintf(i->m.f, " direction=\"%s\"/>\n", direction);
                 else
-                        fputs("/>\n", i->f);
+                        fputs("/>\n", i->m.f);
 
                 signature += l;
         }
@@ -197,6 +211,7 @@ int introspect_write_interface(
         int r;
 
         assert(i);
+        assert(i->m.f);
         assert(interface_name);
 
         r = set_interface_name(i, interface_name);
@@ -216,36 +231,36 @@ int introspect_write_interface(
 
                 case _SD_BUS_VTABLE_START:
                         if (v->flags & SD_BUS_VTABLE_DEPRECATED)
-                                fputs("  <annotation name=\"org.freedesktop.DBus.Deprecated\" value=\"true\"/>\n", i->f);
+                                fputs("  <annotation name=\"org.freedesktop.DBus.Deprecated\" value=\"true\"/>\n", i->m.f);
                         break;
 
                 case _SD_BUS_VTABLE_METHOD:
-                        fprintf(i->f, "  <method name=\"%s\">\n", v->x.method.member);
+                        fprintf(i->m.f, "  <method name=\"%s\">\n", v->x.method.member);
                         if (bus_vtable_has_names(vtable))
                                 names = strempty(v->x.method.names);
                         introspect_write_arguments(i, strempty(v->x.method.signature), &names, "in");
                         introspect_write_arguments(i, strempty(v->x.method.result), &names, "out");
                         introspect_write_flags(i, v->type, v->flags);
-                        fputs("  </method>\n", i->f);
+                        fputs("  </method>\n", i->m.f);
                         break;
 
                 case _SD_BUS_VTABLE_PROPERTY:
                 case _SD_BUS_VTABLE_WRITABLE_PROPERTY:
-                        fprintf(i->f, "  <property name=\"%s\" type=\"%s\" access=\"%s\">\n",
+                        fprintf(i->m.f, "  <property name=\"%s\" type=\"%s\" access=\"%s\">\n",
                                 v->x.property.member,
                                 v->x.property.signature,
                                 v->type == _SD_BUS_VTABLE_WRITABLE_PROPERTY ? "readwrite" : "read");
                         introspect_write_flags(i, v->type, v->flags);
-                        fputs("  </property>\n", i->f);
+                        fputs("  </property>\n", i->m.f);
                         break;
 
                 case _SD_BUS_VTABLE_SIGNAL:
-                        fprintf(i->f, "  <signal name=\"%s\">\n", v->x.signal.member);
+                        fprintf(i->m.f, "  <signal name=\"%s\">\n", v->x.signal.member);
                         if (bus_vtable_has_names(vtable))
                                 names = strempty(v->x.signal.names);
                         introspect_write_arguments(i, strempty(v->x.signal.signature), &names, NULL);
                         introspect_write_flags(i, v->type, v->flags);
-                        fputs("  </signal>\n", i->f);
+                        fputs("  </signal>\n", i->m.f);
                         break;
                 }
 
@@ -255,34 +270,21 @@ int introspect_write_interface(
 }
 
 int introspect_finish(struct introspect *i, char **ret) {
-        int r;
-
         assert(i);
+        assert(i->m.f);
 
         assert_se(set_interface_name(i, NULL) >= 0);
 
-        fputs("</node>\n", i->f);
+        fputs("</node>\n", i->m.f);
 
-        r = fflush_and_check(i->f);
-        if (r < 0)
-                return r;
-
-        i->f = safe_fclose(i->f);
-
-        if (!i->introspection)
-                return -ENOMEM;
-
-        *ret = TAKE_PTR(i->introspection);
-
-        return 0;
+        return memstream_finalize(&i->m, ret, NULL);
 }
 
-void introspect_free(struct introspect *i) {
+void introspect_done(struct introspect *i) {
         assert(i);
 
         /* Normally introspect_finish() does all the work, this is just a backup for error paths */
 
-        safe_fclose(i->f);
+        memstream_done(&i->m);
         free(i->interface_name);
-        free(i->introspection);
 }

src/libsystemd/sd-bus/bus-introspect.h

@@ -5,13 +5,12 @@
 
 #include "sd-bus.h"
 
+#include "memstream-util.h"
 #include "ordered-set.h"
 
 struct introspect {
-        FILE *f;
+        MemStream m;
         char *interface_name;
-        char *introspection;
-        size_t size;
         bool trusted;
 };
 
@@ -23,4 +22,4 @@ int introspect_write_interface(
                 const char *interface_name,
                 const sd_bus_vtable *v);
 int introspect_finish(struct introspect *i, char **ret);
-void introspect_free(struct introspect *i);
+void introspect_done(struct introspect *i);

src/libsystemd/sd-bus/bus-match.c

@@ -7,6 +7,7 @@
 #include "fd-util.h"
 #include "fileio.h"
 #include "hexdecoct.h"
+#include "memstream-util.h"
 #include "sort-util.h"
 #include "string-util.h"
 #include "strv.h"
@@ -823,9 +824,8 @@ int bus_match_parse(
 }
 
 char *bus_match_to_string(struct bus_match_component *components, size_t n_components) {
-        _cleanup_free_ char *buffer = NULL;
-        _cleanup_fclose_ FILE *f = NULL;
-        size_t size = 0;
+        _cleanup_(memstream_done) MemStream m = {};
+        FILE *f;
         int r;
 
         if (n_components <= 0)
@@ -833,7 +833,7 @@ char *bus_match_to_string(struct bus_match_component *components, size_t n_compo
 
         assert(components);
 
-        f = open_memstream_unlocked(&buffer, &size);
+        f = memstream_init(&m);
         if (!f)
                 return NULL;
 
@@ -855,13 +855,12 @@ char *bus_match_to_string(struct bus_match_component *components, size_t n_compo
                 fputc('\'', f);
         }
 
-        r = fflush_and_check(f);
+        char *buffer;
+        r = memstream_finalize(&m, &buffer, NULL);
         if (r < 0)
                 return NULL;
 
-        f = safe_fclose(f);
-
-        return TAKE_PTR(buffer);
+        return buffer;
 }
 
 int bus_match_add(

src/libsystemd/sd-bus/bus-objects.c

@@ -927,7 +927,7 @@ int introspect_path(
                 sd_bus_error *error) {
 
         _cleanup_ordered_set_free_free_ OrderedSet *s = NULL;
-        _cleanup_(introspect_free) struct introspect intro = {};
+        _cleanup_(introspect_done) struct introspect intro = {};
         bool empty;
         int r;
 

src/libsystemd/sd-bus/fuzz-bus-match.c

@@ -7,14 +7,14 @@
 #include "fd-util.h"
 #include "fileio.h"
 #include "fuzz.h"
+#include "memstream-util.h"
 
 DEFINE_TRIVIAL_DESTRUCTOR(bus_match_donep, struct bus_match_node, bus_match_free);
 
 int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
-        _cleanup_free_ char *out = NULL; /* out should be freed after g */
-        size_t out_size;
-        _cleanup_fclose_ FILE *g = NULL;
+        _cleanup_(memstream_done) MemStream m = {};
         _cleanup_(sd_bus_unrefp) sd_bus *bus = NULL;
+        FILE *g = NULL;
         int r;
 
         if (outside_size_range(size, 0, 65536))
@@ -40,7 +40,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         };
 
         if (getenv_bool("SYSTEMD_FUZZ_OUTPUT") <= 0)
-                assert_se(g = open_memstream_unlocked(&out, &out_size));
+                assert_se(g = memstream_init(&m));
 
         for (size_t offset = 0; offset < size; ) {
                 _cleanup_free_ char *line = NULL;

src/libsystemd/sd-bus/fuzz-bus-message.c

@@ -7,14 +7,14 @@
 #include "fd-util.h"
 #include "fileio.h"
 #include "fuzz.h"
+#include "memstream-util.h"
 
 int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
-        _cleanup_free_ char *out = NULL; /* out should be freed after g */
-        size_t out_size;
-        _cleanup_fclose_ FILE *g = NULL;
+        _cleanup_(memstream_done) MemStream ms = {};
         _cleanup_(sd_bus_unrefp) sd_bus *bus = NULL;
         _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = NULL;
         _cleanup_free_ void *buffer = NULL;
+        FILE *g = NULL;
         int r;
 
         /* We don't want to fill the logs with messages about parse errors.
@@ -34,7 +34,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         TAKE_PTR(buffer);
 
         if (getenv_bool("SYSTEMD_FUZZ_OUTPUT") <= 0)
-                assert_se(g = open_memstream_unlocked(&out, &out_size));
+                assert_se(g = memstream_init(&ms));
 
         sd_bus_message_dump(m, g ?: stdout, SD_BUS_MESSAGE_DUMP_WITH_HEADER);
 

src/libsystemd/sd-bus/test-bus-marshal.c

@@ -22,6 +22,7 @@
 #include "fd-util.h"
 #include "fileio.h"
 #include "log.h"
+#include "memstream-util.h"
 #include "tests.h"
 
 static void test_bus_path_encode_unique(void) {
@@ -108,20 +109,19 @@ static void test_bus_label_escape(void) {
 
 int main(int argc, char *argv[]) {
         _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = NULL, *copy = NULL;
-        int r, boolean;
-        const char *x, *x2, *y, *z, *a, *b, *c, *d, *a_signature;
-        uint8_t u, v;
-        void *buffer = NULL;
-        size_t sz;
-        _cleanup_free_ char *h = NULL;
+        _cleanup_free_ char *h = NULL, *first = NULL, *second = NULL, *third = NULL;
         const int32_t integer_array[] = { -1, -2, 0, 1, 2 }, *return_array;
-        char *s;
-        _cleanup_free_ char *first = NULL, *second = NULL, *third = NULL;
-        _cleanup_fclose_ FILE *ms = NULL;
-        size_t first_size = 0, second_size = 0, third_size = 0;
+        const char *x, *x2, *y, *z, *a, *b, *c, *d, *a_signature;
+        size_t sz, first_size, second_size = 0, third_size = 0;
         _cleanup_(sd_bus_unrefp) sd_bus *bus = NULL;
-        double dbl;
+        _cleanup_(memstream_done) MemStream ms = {};
+        void *buffer = NULL;
+        int r, boolean;
         uint64_t u64;
+        uint8_t u, v;
+        double dbl;
+        FILE *mf;
+        char *s;
 
         test_setup_logging(LOG_INFO);
 
@@ -191,10 +191,9 @@ int main(int argc, char *argv[]) {
 
         sd_bus_message_dump(m, stdout, SD_BUS_MESSAGE_DUMP_WITH_HEADER);
 
-        ms = open_memstream_unlocked(&first, &first_size);
-        sd_bus_message_dump(m, ms, 0);
-        fflush(ms);
-        assert_se(!ferror(ms));
+        assert_se(mf = memstream_init(&ms));
+        sd_bus_message_dump(m, mf, 0);
+        assert_se(memstream_finalize(&ms, &first, &first_size) >= 0);
 
         r = bus_message_get_blob(m, &buffer, &sz);
         assert_se(r >= 0);
@@ -247,11 +246,9 @@ int main(int argc, char *argv[]) {
 
         sd_bus_message_dump(m, stdout, SD_BUS_MESSAGE_DUMP_WITH_HEADER);
 
-        fclose(ms);
-        ms = open_memstream_unlocked(&second, &second_size);
-        sd_bus_message_dump(m, ms, 0);
-        fflush(ms);
-        assert_se(!ferror(ms));
+        assert_se(mf = memstream_init(&ms));
+        sd_bus_message_dump(m, mf, 0);
+        assert_se(memstream_finalize(&ms, &second, &second_size) >= 0);
         assert_se(first_size == second_size);
         assert_se(memcmp(first, second, first_size) == 0);
 
@@ -353,11 +350,9 @@ int main(int argc, char *argv[]) {
         r = sd_bus_message_seal(copy, 4712, 0);
         assert_se(r >= 0);
 
-        fclose(ms);
-        ms = open_memstream_unlocked(&third, &third_size);
-        sd_bus_message_dump(copy, ms, 0);
-        fflush(ms);
-        assert_se(!ferror(ms));
+        assert_se(mf = memstream_init(&ms));
+        sd_bus_message_dump(copy, mf, 0);
+        assert_se(memstream_finalize(&ms, &third, &third_size) >= 0);
 
         printf("<%.*s>\n", (int) first_size, first);
         printf("<%.*s>\n", (int) third_size, third);

src/libsystemd/sd-device/test-sd-device.c

@@ -266,7 +266,7 @@ static void test_sd_device_enumerator_filter_subsystem_one(
 
 static bool test_sd_device_enumerator_filter_subsystem_trial(void) {
         _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
-        _cleanup_(hashmap_freep) Hashmap *subsystems = NULL;
+        _cleanup_hashmap_free_ Hashmap *subsystems = NULL;
         unsigned n_new_dev = 0, n_removed_dev = 0;
         sd_device *d;
         Hashmap *h;

src/libsystemd/sd-event/test-event.c

@@ -841,7 +841,7 @@ TEST(leave_ratelimit) {
         bool expect_ratelimit = false, manually_left_ratelimit = false;
         _cleanup_(sd_event_source_unrefp) sd_event_source *s = NULL;
         _cleanup_(sd_event_unrefp) sd_event *e = NULL;
-        _cleanup_(close_pairp) int pfd[2] = PIPE_EBADF;
+        _cleanup_close_pair_ int pfd[2] = PIPE_EBADF;
         unsigned c = 0;
         int r;
 

src/network/generator/network-generator.c

@@ -5,6 +5,7 @@
 #include "hostname-util.h"
 #include "log.h"
 #include "macro.h"
+#include "memstream-util.h"
 #include "netif-naming-scheme.h"
 #include "network-generator.h"
 #include "parse-util.h"
@@ -1198,97 +1199,49 @@ void link_dump(Link *link, FILE *f) {
 }
 
 int network_format(Network *network, char **ret) {
-        _cleanup_free_ char *s = NULL;
-        _cleanup_fclose_ FILE *f = NULL;
-        size_t sz = 0;
-        int r;
+        _cleanup_(memstream_done) MemStream m = {};
+        FILE *f;
 
         assert(network);
         assert(ret);
 
-        f = open_memstream_unlocked(&s, &sz);
+        f = memstream_init(&m);
         if (!f)
                 return -ENOMEM;
 
         network_dump(network, f);
 
-        /* Add terminating 0, so that the output buffer is a valid string. */
-        fputc('\0', f);
-
-        r = fflush_and_check(f);
-        if (r < 0)
-                return r;
-
-        f = safe_fclose(f);
-
-        if (!s)
-                return -ENOMEM;
-
-        *ret = TAKE_PTR(s);
-        assert(sz > 0);
-        return (int) sz - 1;
+        return memstream_finalize(&m, ret, NULL);
 }
 
 int netdev_format(NetDev *netdev, char **ret) {
-        _cleanup_free_ char *s = NULL;
-        _cleanup_fclose_ FILE *f = NULL;
-        size_t sz = 0;
-        int r;
+        _cleanup_(memstream_done) MemStream m = {};
+        FILE *f;
 
         assert(netdev);
         assert(ret);
 
-        f = open_memstream_unlocked(&s, &sz);
+        f = memstream_init(&m);
         if (!f)
                 return -ENOMEM;
 
         netdev_dump(netdev, f);
 
-        /* Add terminating 0, so that the output buffer is a valid string. */
-        fputc('\0', f);
-
-        r = fflush_and_check(f);
-        if (r < 0)
-                return r;
-
-        f = safe_fclose(f);
-
-        if (!s)
-                return -ENOMEM;
-
-        *ret = TAKE_PTR(s);
-        assert(sz > 0);
-        return (int) sz - 1;
+        return memstream_finalize(&m, ret, NULL);
 }
 
 int link_format(Link *link, char **ret) {
-        _cleanup_free_ char *s = NULL;
-        _cleanup_fclose_ FILE *f = NULL;
-        size_t sz = 0;
-        int r;
+        _cleanup_(memstream_done) MemStream m = {};
+        FILE *f;
 
         assert(link);
         assert(ret);
 
-        f = open_memstream_unlocked(&s, &sz);
+        f = memstream_init(&m);
         if (!f)
                 return -ENOMEM;
 
         link_dump(link, f);
 
-        /* Add terminating 0, so that the output buffer is a valid string. */
-        fputc('\0', f);
-
-        r = fflush_and_check(f);
-        if (r < 0)
-                return r;
-
-        f = safe_fclose(f);
-
-        if (!s)
-                return -ENOMEM;
-
-        *ret = TAKE_PTR(s);
-        assert(sz > 0);
-        return (int) sz - 1;
+        return memstream_finalize(&m, ret, NULL);
 }

src/notify/notify.c

@@ -132,7 +132,7 @@ static int parse_argv(int argc, char *argv[]) {
                 {}
         };
 
-        _cleanup_(fdset_freep) FDSet *passed = NULL;
+        _cleanup_fdset_free_ FDSet *passed = NULL;
         bool do_exec = false;
         int c, r, n_env;
 

src/oom/oomd-manager.c

@@ -10,6 +10,7 @@
 #include "fileio.h"
 #include "format-util.h"
 #include "memory-util.h"
+#include "memstream-util.h"
 #include "oomd-manager-bus.h"
 #include "oomd-manager.h"
 #include "path-util.h"
@@ -807,19 +808,16 @@ int manager_start(
 }
 
 int manager_get_dump_string(Manager *m, char **ret) {
-        _cleanup_free_ char *dump = NULL;
-        _cleanup_fclose_ FILE *f = NULL;
+        _cleanup_(memstream_done) MemStream ms = {};
         OomdCGroupContext *c;
-        size_t size;
-        char *key;
-        int r;
+        FILE *f;
 
         assert(m);
         assert(ret);
 
-        f = open_memstream_unlocked(&dump, &size);
+        f = memstream_init(&ms);
         if (!f)
-                return -errno;
+                return -ENOMEM;
 
         fprintf(f,
                 "Dry Run: %s\n"
@@ -834,22 +832,12 @@ int manager_get_dump_string(Manager *m, char **ret) {
         oomd_dump_system_context(&m->system_context, f, "\t");
 
         fprintf(f, "Swap Monitored CGroups:\n");
-        HASHMAP_FOREACH_KEY(c, key, m->monitored_swap_cgroup_contexts)
+        HASHMAP_FOREACH(c, m->monitored_swap_cgroup_contexts)
                 oomd_dump_swap_cgroup_context(c, f, "\t");
 
         fprintf(f, "Memory Pressure Monitored CGroups:\n");
-        HASHMAP_FOREACH_KEY(c, key, m->monitored_mem_pressure_cgroup_contexts)
+        HASHMAP_FOREACH(c, m->monitored_mem_pressure_cgroup_contexts)
                 oomd_dump_memory_pressure_cgroup_context(c, f, "\t");
 
-        r = fflush_and_check(f);
-        if (r < 0)
-                return r;
-
-        f = safe_fclose(f);
-
-        if (!dump)
-                return -ENOMEM;
-
-        *ret = TAKE_PTR(dump);
-        return 0;
+        return memstream_finalize(&ms, ret, NULL);
 }

src/oom/oomd-util.c

@@ -7,6 +7,7 @@
 #include "fd-util.h"
 #include "fileio.h"
 #include "format-util.h"
+#include "memstream-util.h"
 #include "oomd-util.h"
 #include "parse-util.h"
 #include "path-util.h"
@@ -281,30 +282,20 @@ int oomd_cgroup_kill(const char *path, bool recurse, bool dry_run) {
 typedef void (*dump_candidate_func)(const OomdCGroupContext *ctx, FILE *f, const char *prefix);
 
 static int dump_kill_candidates(OomdCGroupContext **sorted, int n, int dump_until, dump_candidate_func dump_func) {
-        /* Try dumping top offendors, ignoring any errors that might happen. */
-        _cleanup_free_ char *dump = NULL;
-        _cleanup_fclose_ FILE *f = NULL;
-        int r;
-        size_t size;
+        _cleanup_(memstream_done) MemStream m = {};
+        FILE *f;
 
-        f = open_memstream_unlocked(&dump, &size);
+        /* Try dumping top offendors, ignoring any errors that might happen. */
+
+        f = memstream_init(&m);
         if (!f)
-                return -errno;
+                return -ENOMEM;
 
         fprintf(f, "Considered %d cgroups for killing, top candidates were:\n", n);
         for (int i = 0; i < dump_until; i++)
                 dump_func(sorted[i], f, "\t");
 
-        r = fflush_and_check(f);
-        if (r < 0)
-                return r;
-
-        f = safe_fclose(f);
-
-        if (!dump)
-                return -ENOMEM;
-
-        return log_dump(LOG_INFO, dump);
+        return memstream_dump(LOG_INFO, &m);
 }
 
 int oomd_kill_by_pgscan_rate(Hashmap *h, const char *prefix, bool dry_run, char **ret_selected) {

src/partition/repart.c

@@ -5261,7 +5261,7 @@ static int resolve_copy_blocks_auto(
 
         const char *try1 = NULL, *try2 = NULL;
         char p[SYS_BLOCK_PATH_MAX("/slaves")];
-        _cleanup_(closedirp) DIR *d = NULL;
+        _cleanup_closedir_ DIR *d = NULL;
         sd_id128_t found_uuid = SD_ID128_NULL;
         dev_t devno, found = 0;
         int r;

src/portable/portable.c

@@ -357,7 +357,7 @@ static int portable_extract_by_path(
         else {
                 _cleanup_(dissected_image_unrefp) DissectedImage *m = NULL;
                 _cleanup_(rmdir_and_freep) char *tmpdir = NULL;
-                _cleanup_(close_pairp) int seq[2] = PIPE_EBADF;
+                _cleanup_close_pair_ int seq[2] = PIPE_EBADF;
                 _cleanup_(sigkill_waitp) pid_t child = 0;
 
                 /* We now have a loopback block device, let's fork off a child in its own mount namespace, mount it
@@ -689,7 +689,7 @@ int portable_extract(
         _cleanup_(portable_metadata_unrefp) PortableMetadata *os_release = NULL;
         _cleanup_ordered_hashmap_free_ OrderedHashmap *extension_images = NULL, *extension_releases = NULL;
         _cleanup_hashmap_free_ Hashmap *unit_files = NULL;
-        _cleanup_(strv_freep) char **valid_prefixes = NULL;
+        _cleanup_strv_free_ char **valid_prefixes = NULL;
         _cleanup_(image_unrefp) Image *image = NULL;
         int r;
 

src/pstore/pstore.c

@@ -281,7 +281,7 @@ static int process_dmesg_files(PStoreList *list) {
 }
 
 static int list_files(PStoreList *list, const char *sourcepath) {
-        _cleanup_(closedirp) DIR *dirp = NULL;
+        _cleanup_closedir_ DIR *dirp = NULL;
         int r;
 
         dirp = opendir(sourcepath);

src/resolve/fuzz-resource-record.c

@@ -3,14 +3,14 @@
 #include "fd-util.h"
 #include "fuzz.h"
 #include "memory-util.h"
+#include "memstream-util.h"
 #include "resolved-dns-packet.h"
 
 int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
-        _cleanup_free_ char *out = NULL; /* out should be freed after f */
-        size_t out_size;
-        _cleanup_fclose_ FILE *f = NULL;
         _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL, *copy = NULL;
         _cleanup_(json_variant_unrefp) JsonVariant *v = NULL;
+        _cleanup_(memstream_done) MemStream m = {};
+        FILE *f;
 
         if (outside_size_range(size, 0, DNS_PACKET_SIZE_MAX))
                 return 0;
@@ -21,7 +21,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         assert_se(copy = dns_resource_record_copy(rr));
         assert_se(dns_resource_record_equal(copy, rr) > 0);
 
-        assert_se(f = open_memstream_unlocked(&out, &out_size));
+        assert_se(f = memstream_init(&m));
         (void) fprintf(f, "%s", strna(dns_resource_record_to_string(rr)));
 
         if (dns_resource_record_to_json(rr, &v) < 0)

src/resolve/resolved-dns-dnssec.c

@@ -7,6 +7,7 @@
 #include "gcrypt-util.h"
 #include "hexdecoct.h"
 #include "memory-util.h"
+#include "memstream-util.h"
 #include "openssl-util.h"
 #include "resolved-dns-dnssec.h"
 #include "resolved-dns-packet.h"
@@ -810,11 +811,10 @@ static int dnssec_rrset_serialize_sig(
                 char **ret_sig_data,
                 size_t *ret_sig_size) {
 
-        _cleanup_free_ char *sig_data = NULL;
-        size_t sig_size = 0;
-        _cleanup_fclose_ FILE *f = NULL;
+        _cleanup_(memstream_done) MemStream m = {};
         uint8_t wire_format_name[DNS_WIRE_FORMAT_HOSTNAME_MAX];
         DnsResourceRecord *rr;
+        FILE *f;
         int r;
 
         assert(rrsig);
@@ -823,7 +823,7 @@ static int dnssec_rrset_serialize_sig(
         assert(ret_sig_data);
         assert(ret_sig_size);
 
-        f = open_memstream_unlocked(&sig_data, &sig_size);
+        f = memstream_init(&m);
         if (!f)
                 return -ENOMEM;
 
@@ -866,18 +866,7 @@ static int dnssec_rrset_serialize_sig(
                 fwrite(DNS_RESOURCE_RECORD_RDATA(rr), 1, l, f);
         }
 
-        r = fflush_and_check(f);
-        if (r < 0)
-                return r;
-
-        f = safe_fclose(f);  /* sig_data may be reallocated when f is closed. */
-
-        if (!sig_data)
-                return -ENOMEM;
-
-        *ret_sig_data = TAKE_PTR(sig_data);
-        *ret_sig_size = sig_size;
-        return 0;
+        return memstream_finalize(&m, ret_sig_data, ret_sig_size);
 }
 
 static int dnssec_rrset_verify_sig(

src/resolve/resolved-manager.c

@@ -19,6 +19,7 @@
 #include "hostname-util.h"
 #include "idn-util.h"
 #include "io-util.h"
+#include "memstream-util.h"
 #include "missing_network.h"
 #include "missing_socket.h"
 #include "netlink-util.h"
@@ -492,16 +493,15 @@ static int manager_watch_hostname(Manager *m) {
 }
 
 static int manager_sigusr1(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {
-        _cleanup_free_ char *buffer = NULL;
-        _cleanup_fclose_ FILE *f = NULL;
+        _cleanup_(memstream_done) MemStream ms = {};
         Manager *m = ASSERT_PTR(userdata);
-        size_t size = 0;
         Link *l;
+        FILE *f;
 
         assert(s);
         assert(si);
 
-        f = open_memstream_unlocked(&buffer, &size);
+        f = memstream_init(&ms);
         if (!f)
                 return log_oom();
 
@@ -516,16 +516,7 @@ static int manager_sigusr1(sd_event_source *s, const struct signalfd_siginfo *si
                 LIST_FOREACH(servers, server, l->dns_servers)
                         dns_server_dump(server, f);
 
-        if (fflush_and_check(f) < 0)
-                return log_oom();
-
-        f = safe_fclose(f);
-
-        if (!buffer)
-                return -ENOMEM;
-
-        log_dump(LOG_INFO, buffer);
-        return 0;
+        return memstream_dump(LOG_INFO, &ms);
 }
 
 static int manager_sigusr2(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {

src/shared/bootspec.c

@@ -854,7 +854,7 @@ static int boot_entries_find_unified(
                 const char *root,
                 const char *dir) {
 
-        _cleanup_(closedirp) DIR *d = NULL;
+        _cleanup_closedir_ DIR *d = NULL;
         _cleanup_free_ char *full = NULL;
         int r;
 

src/shared/bus-util.c

@@ -20,6 +20,7 @@
 #include "bus-util.h"
 #include "data-fd-util.h"
 #include "fd-util.h"
+#include "memstream-util.h"
 #include "path-util.h"
 #include "socket-util.h"
 #include "stdio-util.h"
@@ -610,26 +611,26 @@ int bus_reply_pair_array(sd_bus_message *m, char **l) {
 }
 
 static int method_dump_memory_state_by_fd(sd_bus_message *message, void *userdata, sd_bus_error *ret_error) {
-        _cleanup_free_ char *dump = NULL; /* keep this above dump_file, so that it's freed after */
-        _cleanup_fclose_ FILE *dump_file = NULL;
+        _cleanup_(memstream_done) MemStream m = {};
+        _cleanup_free_ char *dump = NULL;
         _cleanup_close_ int fd = -EBADF;
         size_t dump_size;
+        FILE *f;
         int r;
 
         assert(message);
 
-        dump_file = open_memstream(&dump, &dump_size);
-        if (!dump_file)
+        f = memstream_init(&m);
+        if (!f)
                 return -ENOMEM;
 
-        r = RET_NERRNO(malloc_info(/* options= */ 0, dump_file));
+        r = RET_NERRNO(malloc_info(/* options= */ 0, f));
         if (r < 0)
                 return r;
 
-        dump_file = safe_fclose(dump_file);
-
-        if (!dump)
-                return -ENOMEM;
+        r = memstream_finalize(&m, &dump, &dump_size);
+        if (r < 0)
+                return r;
 
         fd = acquire_data_fd(dump, dump_size, 0);
         if (fd < 0)

src/shared/calendarspec.c

@@ -15,6 +15,7 @@
 #include "fd-util.h"
 #include "fileio.h"
 #include "macro.h"
+#include "memstream-util.h"
 #include "parse-util.h"
 #include "process-util.h"
 #include "sort-util.h"
@@ -336,16 +337,14 @@ static void format_chain(FILE *f, int space, const CalendarComponent *c, bool us
         _format_chain(f, space, c, /* start = */ true, usec);
 }
 
-int calendar_spec_to_string(const CalendarSpec *c, char **p) {
-        _cleanup_free_ char *buf = NULL;
-        _cleanup_fclose_ FILE *f = NULL;
-        size_t sz = 0;
-        int r;
+int calendar_spec_to_string(const CalendarSpec *c, char **ret) {
+        _cleanup_(memstream_done) MemStream m = {};
+        FILE *f;
 
         assert(c);
-        assert(p);
+        assert(ret);
 
-        f = open_memstream_unlocked(&buf, &sz);
+        f = memstream_init(&m);
         if (!f)
                 return -ENOMEM;
 
@@ -383,17 +382,7 @@ int calendar_spec_to_string(const CalendarSpec *c, char **p) {
                 }
         }
 
-        r = fflush_and_check(f);
-        if (r < 0)
-                return r;
-
-        f = safe_fclose(f);
-
-        if (!buf)
-                return -ENOMEM;
-
-        *p = TAKE_PTR(buf);
-        return 0;
+        return memstream_finalize(&m, ret, NULL);
 }
 
 static int parse_weekdays(const char **p, CalendarSpec *c) {
@@ -879,7 +868,7 @@ finish:
         return 0;
 }
 
-int calendar_spec_from_string(const char *p, CalendarSpec **spec) {
+int calendar_spec_from_string(const char *p, CalendarSpec **ret) {
         const char *utc;
         _cleanup_(calendar_spec_freep) CalendarSpec *c = NULL;
         _cleanup_free_ char *p_tmp = NULL;
@@ -1099,8 +1088,8 @@ int calendar_spec_from_string(const char *p, CalendarSpec **spec) {
         if (!calendar_spec_valid(c))
                 return -EINVAL;
 
-        if (spec)
-                *spec = TAKE_PTR(c);
+        if (ret)
+                *ret = TAKE_PTR(c);
         return 0;
 }
 

src/shared/calendarspec.h

@@ -36,8 +36,8 @@ CalendarSpec* calendar_spec_free(CalendarSpec *c);
 
 bool calendar_spec_valid(CalendarSpec *spec);
 
-int calendar_spec_to_string(const CalendarSpec *spec, char **p);
-int calendar_spec_from_string(const char *p, CalendarSpec **spec);
+int calendar_spec_to_string(const CalendarSpec *spec, char **ret);
+int calendar_spec_from_string(const char *p, CalendarSpec **ret);
 
 int calendar_spec_next_usec(const CalendarSpec *spec, usec_t usec, usec_t *next);
 

src/shared/common-signal.c

@@ -3,13 +3,13 @@
 #include "common-signal.h"
 #include "fd-util.h"
 #include "fileio.h"
+#include "memstream-util.h"
 #include "process-util.h"
 #include "signal-util.h"
 
 int sigrtmin18_handler(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {
         struct sigrtmin18_info *info = userdata;
         _cleanup_free_ char *comm = NULL;
-        int r;
 
         assert(s);
         assert(si);
@@ -57,11 +57,10 @@ int sigrtmin18_handler(sd_event_source *s, const struct signalfd_siginfo *si, vo
                 break;
 
         case COMMON_SIGNAL_COMMAND_MALLOC_INFO: {
-                _cleanup_free_ char *data = NULL;
-                _cleanup_fclose_ FILE *f = NULL;
-                size_t sz;
+                _cleanup_(memstream_done) MemStream m = {};
+                FILE *f;
 
-                f = open_memstream_unlocked(&data, &sz);
+                f = memstream_init(&m);
                 if (!f) {
                         log_oom();
                         break;
@@ -72,15 +71,7 @@ int sigrtmin18_handler(sd_event_source *s, const struct signalfd_siginfo *si, vo
                         break;
                 }
 
-                fputc(0, f);
-
-                r = fflush_and_check(f);
-                if (r < 0) {
-                        log_error_errno(r, "Failed to flush malloc_info() buffer: %m");
-                        break;
-                }
-
-                log_dump(LOG_INFO, data);
+                (void) memstream_dump(LOG_INFO, &m);
                 break;
         }
 

src/shared/data-fd-util.c

@@ -206,7 +206,7 @@ int copy_data_fd(int fd) {
                         /* Hmm, pity, this didn't fit. Let's fall back to /tmp then, see below */
 
                 } else {
-                        _cleanup_(close_pairp) int pipefds[2] = PIPE_EBADF;
+                        _cleanup_close_pair_ int pipefds[2] = PIPE_EBADF;
                         int isz;
 
                         /* If memfds aren't available, use a pipe. Set O_NONBLOCK so that we will get EAGAIN rather

src/shared/elf-util.c

@@ -22,6 +22,7 @@
 #include "hexdecoct.h"
 #include "io-util.h"
 #include "macro.h"
+#include "memstream-util.h"
 #include "process-util.h"
 #include "rlimit-util.h"
 #include "string-util.h"
@@ -149,7 +150,7 @@ int dlopen_elf(void) {
 }
 
 typedef struct StackContext {
-        FILE *f;
+        MemStream m;
         Dwfl *dwfl;
         Elf *elf;
         unsigned n_thread;
@@ -158,11 +159,10 @@ typedef struct StackContext {
         Set **modules;
 } StackContext;
 
-static StackContext* stack_context_destroy(StackContext *c) {
-        if (!c)
-                return NULL;
+static void stack_context_done(StackContext *c) {
+        assert(c);
 
-        c->f = safe_fclose(c->f);
+        memstream_done(&c->m);
 
         if (c->dwfl) {
                 sym_dwfl_end(c->dwfl);
@@ -173,8 +173,6 @@ static StackContext* stack_context_destroy(StackContext *c) {
                 sym_elf_end(c->elf);
                 c->elf = NULL;
         }
-
-        return NULL;
 }
 
 DEFINE_TRIVIAL_CLEANUP_FUNC_FULL(Elf *, sym_elf_end, NULL);
@@ -235,8 +233,8 @@ static int frame_callback(Dwfl_Frame *frame, void *userdata) {
                 module_offset = pc - start;
         }
 
-        if (c->f)
-                fprintf(c->f, "#%-2u 0x%016" PRIx64 " %s (%s + 0x%" PRIx64 ")\n", c->n_frame, (uint64_t) pc, strna(symbol), strna(fname), module_offset);
+        if (c->m.f)
+                fprintf(c->m.f, "#%-2u 0x%016" PRIx64 " %s (%s + 0x%" PRIx64 ")\n", c->n_frame, (uint64_t) pc, strna(symbol), strna(fname), module_offset);
         c->n_frame++;
 
         return DWARF_CB_OK;
@@ -251,14 +249,14 @@ static int thread_callback(Dwfl_Thread *thread, void *userdata) {
         if (c->n_thread >= THREADS_MAX)
                 return DWARF_CB_ABORT;
 
-        if (c->n_thread != 0 && c->f)
-                fputc('\n', c->f);
+        if (c->n_thread != 0 && c->m.f)
+                fputc('\n', c->m.f);
 
         c->n_frame = 0;
 
-        if (c->f) {
+        if (c->m.f) {
                 tid = sym_dwfl_thread_tid(thread);
-                fprintf(c->f, "Stack trace of thread " PID_FMT ":\n", tid);
+                fprintf(c->m.f, "Stack trace of thread " PID_FMT ":\n", tid);
         }
 
         if (sym_dwfl_thread_getframes(thread, frame_callback, c) < 0)
@@ -297,10 +295,10 @@ static void report_module_metadata(StackContext *c, const char *name, JsonVarian
         assert(c);
         assert(name);
 
-        if (!c->f)
+        if (!c->m.f)
                 return;
 
-        fprintf(c->f, "Module %s", name);
+        fprintf(c->m.f, "Module %s", name);
 
         if (metadata) {
                 const char
@@ -314,14 +312,14 @@ static void report_module_metadata(StackContext *c, const char *name, JsonVarian
                         /* Version/architecture is only meaningful with a package name.
                          * Skip the detailed fields if package is unknown. */
                         _cleanup_free_ char *id = build_package_reference(type, package, version, arch);
-                        fprintf(c->f, " from %s", strnull(id));
+                        fprintf(c->m.f, " from %s", strnull(id));
                 }
 
                 if (build_id && !(package && version))
-                        fprintf(c->f, ", build-id=%s", build_id);
+                        fprintf(c->m.f, ", build-id=%s", build_id);
         }
 
-        fputs("\n", c->f);
+        fputs("\n", c->m.f);
 }
 
 static int parse_package_metadata(const char *name, JsonVariant *id_json, Elf *elf, bool *ret_interpreter_found, StackContext *c) {
@@ -464,8 +462,8 @@ static int parse_buildid(Dwfl_Module *mod, Elf *elf, const char *name, StackCont
                 /* If we don't find a build-id, note it in the journal message, and try
                  * anyway to find the package metadata. It's unlikely to have the latter
                  * without the former, but there's no hard rule. */
-                if (c->f)
-                        fprintf(c->f, "Module %s without build-id.\n", name);
+                if (c->m.f)
+                        fprintf(c->m.f, "Module %s without build-id.\n", name);
         } else {
                 /* We will later parse package metadata json and pass it to our caller. Prepare the
                 * build-id in json format too, so that it can be appended and parsed cleanly. It
@@ -570,13 +568,11 @@ static int parse_core(int fd, const char *executable, char **ret, JsonVariant **
         };
 
         _cleanup_(json_variant_unrefp) JsonVariant *package_metadata = NULL;
-        _cleanup_(set_freep) Set *modules = NULL;
-        _cleanup_free_ char *buf = NULL; /* buf should be freed last, c.f closed first (via stack_context_destroy) */
-        _cleanup_(stack_context_destroy) StackContext c = {
+        _cleanup_set_free_ Set *modules = NULL;
+        _cleanup_(stack_context_done) StackContext c = {
                 .package_metadata = &package_metadata,
                 .modules = &modules,
         };
-        size_t sz = 0;
         int r;
 
         assert(fd >= 0);
@@ -584,11 +580,8 @@ static int parse_core(int fd, const char *executable, char **ret, JsonVariant **
         if (lseek(fd, 0, SEEK_SET) == (off_t) -1)
                 return log_warning_errno(errno, "Failed to seek to beginning of the core file: %m");
 
-        if (ret) {
-                c.f = open_memstream_unlocked(&buf, &sz);
-                if (!c.f)
-                        return log_oom();
-        }
+        if (ret && !memstream_init(&c.m))
+                return log_oom();
 
         sym_elf_version(EV_CURRENT);
 
@@ -616,16 +609,9 @@ static int parse_core(int fd, const char *executable, char **ret, JsonVariant **
                 return log_warning_errno(SYNTHETIC_ERRNO(EINVAL), "Could not parse core file, dwfl_getthreads() failed: %s", sym_dwfl_errmsg(sym_dwfl_errno()));
 
         if (ret) {
-                r = fflush_and_check(c.f);
+                r = memstream_finalize(&c.m, ret, NULL);
                 if (r < 0)
                         return log_warning_errno(r, "Could not parse core file, flushing file buffer failed: %m");
-
-                c.f = safe_fclose(c.f);
-
-                if (!buf)
-                        return log_oom();
-
-                *ret = TAKE_PTR(buf);
         }
 
         if (ret_package_metadata)
@@ -636,15 +622,13 @@ static int parse_core(int fd, const char *executable, char **ret, JsonVariant **
 
 static int parse_elf(int fd, const char *executable, char **ret, JsonVariant **ret_package_metadata) {
         _cleanup_(json_variant_unrefp) JsonVariant *package_metadata = NULL, *elf_metadata = NULL;
-        _cleanup_(set_freep) Set *modules = NULL;
-        _cleanup_free_ char *buf = NULL; /* buf should be freed last, c.f closed first (via stack_context_destroy) */
-        _cleanup_(stack_context_destroy) StackContext c = {
+        _cleanup_set_free_ Set *modules = NULL;
+        _cleanup_(stack_context_done) StackContext c = {
                 .package_metadata = &package_metadata,
                 .modules = &modules,
         };
         const char *elf_type;
         GElf_Ehdr elf_header;
-        size_t sz = 0;
         int r;
 
         assert(fd >= 0);
@@ -652,11 +636,8 @@ static int parse_elf(int fd, const char *executable, char **ret, JsonVariant **r
         if (lseek(fd, 0, SEEK_SET) == (off_t) -1)
                 return log_warning_errno(errno, "Failed to seek to beginning of the ELF file: %m");
 
-        if (ret) {
-                c.f = open_memstream_unlocked(&buf, &sz);
-                if (!c.f)
-                        return log_oom();
-        }
+        if (ret && !memstream_init(&c.m))
+                return log_oom();
 
         sym_elf_version(EV_CURRENT);
 
@@ -675,7 +656,7 @@ static int parse_elf(int fd, const char *executable, char **ret, JsonVariant **r
                         return log_warning_errno(r, "Failed to inspect core file: %m");
 
                 if (out)
-                        fprintf(c.f, "%s", out);
+                        fprintf(c.m.f, "%s", out);
 
                 elf_type = "coredump";
         } else {
@@ -725,7 +706,7 @@ static int parse_elf(int fd, const char *executable, char **ret, JsonVariant **r
                         return log_warning_errno(r, "Failed to merge JSON objects: %m");
 
                 if (ret)
-                        fprintf(c.f, "ELF object binary architecture: %s\n", elf_architecture);
+                        fprintf(c.m.f, "ELF object binary architecture: %s\n", elf_architecture);
         }
 #endif
 
@@ -735,16 +716,9 @@ static int parse_elf(int fd, const char *executable, char **ret, JsonVariant **r
                 return log_warning_errno(r, "Failed to merge JSON objects: %m");
 
         if (ret) {
-                r = fflush_and_check(c.f);
+                r = memstream_finalize(&c.m, ret, NULL);
                 if (r < 0)
                         return log_warning_errno(r, "Could not parse ELF file, flushing file buffer failed: %m");
-
-                c.f = safe_fclose(c.f);
-
-                if (!buf)
-                        return log_oom();
-
-                *ret = TAKE_PTR(buf);
         }
 
         if (ret_package_metadata)

src/shared/format-table.c

@@ -18,6 +18,7 @@
 #include "id128-util.h"
 #include "in-addr-util.h"
 #include "memory-util.h"
+#include "memstream-util.h"
 #include "pager.h"
 #include "parse-util.h"
 #include "path-util.h"
@@ -1446,11 +1447,10 @@ static int table_data_compare(const size_t *a, const size_t *b, Table *t) {
 }
 
 static char* format_strv_width(char **strv, size_t column_width) {
-        _cleanup_free_ char *buf = NULL; /* buf must be freed after f */
-        _cleanup_fclose_ FILE *f = NULL;
-        size_t sz = 0;
+        _cleanup_(memstream_done) MemStream m = {};
+        FILE *f;
 
-        f = open_memstream_unlocked(&buf, &sz);
+        f = memstream_init(&m);
         if (!f)
                 return NULL;
 
@@ -1471,11 +1471,11 @@ static char* format_strv_width(char **strv, size_t column_width) {
                 }
         }
 
-        if (fflush_and_check(f) < 0)
+        char *buf;
+        if (memstream_finalize(&m, &buf, NULL) < 0)
                 return NULL;
 
-        f = safe_fclose(f);
-        return TAKE_PTR(buf);
+        return buf;
 }
 
 static const char *table_data_format(Table *t, TableData *d, bool avoid_uppercasing, size_t column_width, bool *have_soft) {
@@ -2530,12 +2530,14 @@ int table_print(Table *t, FILE *f) {
 }
 
 int table_format(Table *t, char **ret) {
-        _cleanup_free_ char *buf = NULL;
-        _cleanup_fclose_ FILE *f = NULL;
-        size_t sz = 0;
+        _cleanup_(memstream_done) MemStream m = {};
+        FILE *f;
         int r;
 
-        f = open_memstream_unlocked(&buf, &sz);
+        assert(t);
+        assert(ret);
+
+        f = memstream_init(&m);
         if (!f)
                 return -ENOMEM;
 
@@ -2543,14 +2545,7 @@ int table_format(Table *t, char **ret) {
         if (r < 0)
                 return r;
 
-        f = safe_fclose(f);
-
-        if (!buf)
-                return -ENOMEM;
-
-        *ret = TAKE_PTR(buf);
-
-        return 0;
+        return memstream_finalize(&m, ret, NULL);
 }
 
 size_t table_get_rows(Table *t) {

src/shared/json.c

@@ -20,6 +20,7 @@
 #include "macro.h"
 #include "math-util.h"
 #include "memory-util.h"
+#include "memstream-util.h"
 #include "string-table.h"
 #include "string-util.h"
 #include "strv.h"
@@ -1768,9 +1769,9 @@ static int json_format(FILE *f, JsonVariant *v, JsonFormatFlags flags, const cha
 }
 
 int json_variant_format(JsonVariant *v, JsonFormatFlags flags, char **ret) {
-        _cleanup_free_ char *s = NULL;
-        _cleanup_fclose_ FILE *f = NULL;
-        size_t sz = 0;
+        _cleanup_(memstream_done) MemStream m = {};
+        size_t sz;
+        FILE *f;
         int r;
 
         /* Returns the length of the generated string (without the terminating NUL),
@@ -1782,7 +1783,7 @@ int json_variant_format(JsonVariant *v, JsonFormatFlags flags, char **ret) {
         if (flags & JSON_FORMAT_OFF)
                 return -ENOEXEC;
 
-        f = open_memstream_unlocked(&s, &sz);
+        f = memstream_init(&m);
         if (!f)
                 return -ENOMEM;
 
@@ -1790,21 +1791,11 @@ int json_variant_format(JsonVariant *v, JsonFormatFlags flags, char **ret) {
         if (r < 0)
                 return r;
 
-        /* Add terminating 0, so that the output buffer is a valid string. */
-        fputc('\0', f);
-
-        r = fflush_and_check(f);
+        r = memstream_finalize(&m, ret, &sz);
         if (r < 0)
                 return r;
 
-        f = safe_fclose(f);
-
-        if (!s)
-                return -ENOMEM;
-
-        *ret = TAKE_PTR(s);
-        assert(sz > 0);
-        return (int) sz - 1;
+        return sz;
 }
 
 int json_variant_dump(JsonVariant *v, JsonFormatFlags flags, FILE *f, const char *prefix) {

src/shared/kbd-util.c

@@ -64,7 +64,7 @@ static int keymap_recurse_dir_callback(
 }
 
 int get_keymaps(char ***ret) {
-        _cleanup_(set_free_freep) Set *keymaps = NULL;
+        _cleanup_set_free_free_ Set *keymaps = NULL;
         int r;
 
         keymaps = set_new(&string_hash_ops);

src/shared/libfido2-util.c

@@ -820,7 +820,7 @@ int fido2_generate_hmac_hash(
                                                "Token asks for PIN but doesn't advertise 'clientPin' feature.");
 
                 for (;;) {
-                        _cleanup_(strv_free_erasep) char **pin = NULL;
+                        _cleanup_strv_free_erase_ char **pin = NULL;
 
                         r = ask_password_auto("Please enter security token PIN:", askpw_icon_name, NULL, "fido2-pin", "fido2-pin", USEC_INFINITY, 0, &pin);
                         if (r < 0)

src/shared/mkfs-util.c

@@ -548,7 +548,7 @@ int make_filesystem(
 }
 
 int mkfs_options_from_env(const char *component, const char *fstype, char ***ret) {
-        _cleanup_(strv_freep) char **l = NULL;
+        _cleanup_strv_free_ char **l = NULL;
         const char *e;
         char *n;
 

src/shared/sleep-config.c

@@ -222,7 +222,7 @@ int battery_is_discharging_and_low(void) {
 /* Store current capacity of each battery before suspension and timestamp */
 int fetch_batteries_capacity_by_name(Hashmap **ret) {
         _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
-        _cleanup_(hashmap_freep) Hashmap *batteries_capacity_by_name = NULL;
+        _cleanup_hashmap_free_ Hashmap *batteries_capacity_by_name = NULL;
         sd_device *dev;
         int r;
 

src/shared/tpm2-util.c

@@ -2847,7 +2847,7 @@ int tpm2_unseal(const char *device,
 int tpm2_list_devices(void) {
 #if HAVE_TPM2
         _cleanup_(table_unrefp) Table *t = NULL;
-        _cleanup_(closedirp) DIR *d = NULL;
+        _cleanup_closedir_ DIR *d = NULL;
         int r;
 
         r = dlopen_tpm2();
@@ -2923,7 +2923,7 @@ int tpm2_find_device_auto(
                 int log_level, /* log level when no device is found */
                 char **ret) {
 #if HAVE_TPM2
-        _cleanup_(closedirp) DIR *d = NULL;
+        _cleanup_closedir_ DIR *d = NULL;
         int r;
 
         r = dlopen_tpm2();

src/shared/userdb.c

@@ -395,8 +395,8 @@ static int userdb_start_query(
                 JsonVariant *query,
                 UserDBFlags flags) {
 
-        _cleanup_(strv_freep) char **except = NULL, **only = NULL;
-        _cleanup_(closedirp) DIR *d = NULL;
+        _cleanup_strv_free_ char **except = NULL, **only = NULL;
+        _cleanup_closedir_ DIR *d = NULL;
         const char *e;
         int r, ret = 0;
 

src/shutdown/umount.c

@@ -605,7 +605,7 @@ static void log_umount_blockers(const char *mnt) {
 }
 
 static int remount_with_timeout(MountPoint *m, bool last_try) {
-        _cleanup_(close_pairp) int pfd[2] = PIPE_EBADF;
+        _cleanup_close_pair_ int pfd[2] = PIPE_EBADF;
         _cleanup_(sigkill_nowaitp) pid_t pid = 0;
         int r;
 
@@ -661,7 +661,7 @@ static int remount_with_timeout(MountPoint *m, bool last_try) {
 }
 
 static int umount_with_timeout(MountPoint *m, bool last_try) {
-        _cleanup_(close_pairp) int pfd[2] = PIPE_EBADF;
+        _cleanup_close_pair_ int pfd[2] = PIPE_EBADF;
         _cleanup_(sigkill_nowaitp) pid_t pid = 0;
         int r;
 

src/sysctl/sysctl.c

@@ -443,7 +443,7 @@ static int parse_argv(int argc, char *argv[]) {
 }
 
 static int run(int argc, char *argv[]) {
-        _cleanup_(ordered_hashmap_freep) OrderedHashmap *sysctl_options = NULL;
+        _cleanup_ordered_hashmap_free_ OrderedHashmap *sysctl_options = NULL;
         int r, k;
 
         r = parse_argv(argc, argv);

src/sysext/sysext.c

@@ -788,7 +788,7 @@ static int merge(Hashmap *images) {
 }
 
 static int image_discover_and_read_metadata(Hashmap **ret_images) {
-        _cleanup_(hashmap_freep) Hashmap *images = NULL;
+        _cleanup_hashmap_free_ Hashmap *images = NULL;
         Image *img;
         int r;
 
@@ -814,7 +814,7 @@ static int image_discover_and_read_metadata(Hashmap **ret_images) {
 }
 
 static int verb_merge(int argc, char **argv, void *userdata) {
-        _cleanup_(hashmap_freep) Hashmap *images = NULL;
+        _cleanup_hashmap_free_ Hashmap *images = NULL;
         int r;
 
         r = have_effective_cap(CAP_SYS_ADMIN);
@@ -852,7 +852,7 @@ static int verb_merge(int argc, char **argv, void *userdata) {
 }
 
 static int verb_refresh(int argc, char **argv, void *userdata) {
-        _cleanup_(hashmap_freep) Hashmap *images = NULL;
+        _cleanup_hashmap_free_ Hashmap *images = NULL;
         int r;
 
         r = have_effective_cap(CAP_SYS_ADMIN);
@@ -892,7 +892,7 @@ static int verb_refresh(int argc, char **argv, void *userdata) {
 }
 
 static int verb_list(int argc, char **argv, void *userdata) {
-        _cleanup_(hashmap_freep) Hashmap *images = NULL;
+        _cleanup_hashmap_free_ Hashmap *images = NULL;
         _cleanup_(table_unrefp) Table *t = NULL;
         Image *img;
         int r;

src/systemctl/systemctl-edit.c

@@ -14,7 +14,7 @@
 #include "terminal-util.h"
 
 int verb_cat(int argc, char *argv[], void *userdata) {
-        _cleanup_(hashmap_freep) Hashmap *cached_name_map = NULL, *cached_id_map = NULL;
+        _cleanup_hashmap_free_ Hashmap *cached_name_map = NULL, *cached_id_map = NULL;
         _cleanup_(lookup_paths_free) LookupPaths lp = {};
         _cleanup_strv_free_ char **names = NULL;
         sd_bus *bus;
@@ -197,7 +197,7 @@ static int find_paths_to_edit(
                 EditFileContext *context,
                 char **names) {
 
-        _cleanup_(hashmap_freep) Hashmap *cached_name_map = NULL, *cached_id_map = NULL;
+        _cleanup_hashmap_free_ Hashmap *cached_name_map = NULL, *cached_id_map = NULL;
         _cleanup_(lookup_paths_free) LookupPaths lp = {};
         _cleanup_free_ char *drop_in_alloc = NULL, *suffix = NULL;
         const char *drop_in;

src/systemctl/systemctl-list-unit-files.c

@@ -143,7 +143,7 @@ static int output_unit_file_list(const UnitFileList *units, unsigned c) {
 int verb_list_unit_files(int argc, char *argv[], void *userdata) {
         _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
         _cleanup_free_ UnitFileList *units = NULL;
-        _cleanup_(hashmap_freep) Hashmap *h = NULL;
+        _cleanup_hashmap_free_ Hashmap *h = NULL;
         unsigned c = 0;
         const char *state;
         char *path;

src/sysupdate/sysupdate-resource.c

@@ -72,7 +72,7 @@ static int resource_load_from_directory(
                 Resource *rr,
                 mode_t m) {
 
-        _cleanup_(closedirp) DIR *d = NULL;
+        _cleanup_closedir_ DIR *d = NULL;
         int r;
 
         assert(rr);
@@ -242,7 +242,7 @@ static int download_manifest(
                 size_t *ret_size) {
 
         _cleanup_free_ char *buffer = NULL, *suffixed_url = NULL;
-        _cleanup_(close_pairp) int pfd[2] = PIPE_EBADF;
+        _cleanup_close_pair_ int pfd[2] = PIPE_EBADF;
         _cleanup_fclose_ FILE *manifest = NULL;
         size_t size = 0;
         pid_t pid;

src/sysupdate/sysupdate-transfer.c

@@ -570,7 +570,7 @@ int transfer_resolve_paths(
 }
 
 static void transfer_remove_temporary(Transfer *t) {
-        _cleanup_(closedirp) DIR *d = NULL;
+        _cleanup_closedir_ DIR *d = NULL;
         int r;
 
         assert(t);

src/sysupdate/sysupdate.c

@@ -1093,7 +1093,7 @@ static int component_name_valid(const char *c) {
 static int verb_components(int argc, char **argv, void *userdata) {
         _cleanup_(loop_device_unrefp) LoopDevice *loop_device = NULL;
         _cleanup_(umount_and_rmdir_and_freep) char *mounted_dir = NULL;
-        _cleanup_(set_freep) Set *names = NULL;
+        _cleanup_set_free_ Set *names = NULL;
         _cleanup_free_ char **z = NULL; /* We use simple free() rather than strv_free() here, since set_free() will free the strings for us */
         char **l = CONF_PATHS_STRV("");
         bool has_default_component = false;

src/test/meson.build

@@ -115,6 +115,7 @@ simple_tests += files(
         'test-memfd-util.c',
         'test-memory-util.c',
         'test-mempool.c',
+        'test-memstream-util.c',
         'test-mkdir.c',
         'test-modhex.c',
         'test-mountpoint-util.c',

src/test/test-data-fd-util.c

@@ -81,7 +81,7 @@ static void assert_equal_fd(int fd1, int fd2) {
 
 TEST(copy_data_fd) {
         _cleanup_close_ int fd1 = -EBADF, fd2 = -EBADF;
-        _cleanup_(close_pairp) int sfd[2] = PIPE_EBADF;
+        _cleanup_close_pair_ int sfd[2] = PIPE_EBADF;
         _cleanup_(sigkill_waitp) pid_t pid = -1;
         int r;
 

src/test/test-hashmap-plain.c

@@ -11,7 +11,7 @@
 #include "tests.h"
 
 TEST(hashmap_replace) {
-        _cleanup_(hashmap_freep) Hashmap *m = NULL;
+        _cleanup_hashmap_free_ Hashmap *m = NULL;
         _cleanup_free_ char *val1 = NULL, *val2 = NULL, *val3 = NULL, *val4 = NULL, *val5 = NULL;
         char *r;
 
@@ -43,8 +43,8 @@ TEST(hashmap_replace) {
 }
 
 TEST(hashmap_copy) {
-        _cleanup_(hashmap_freep) Hashmap *m = NULL;
-        _cleanup_(hashmap_free_freep) Hashmap *copy = NULL;
+        _cleanup_hashmap_free_ Hashmap *m = NULL;
+        _cleanup_hashmap_free_free_ Hashmap *copy = NULL;
         char *val1, *val2, *val3, *val4, *r;
 
         val1 = strdup("val1");
@@ -76,8 +76,8 @@ TEST(hashmap_copy) {
 }
 
 TEST(hashmap_get_strv) {
-        _cleanup_(hashmap_freep) Hashmap *m = NULL;
-        _cleanup_(strv_freep) char **strv = NULL;
+        _cleanup_hashmap_free_ Hashmap *m = NULL;
+        _cleanup_strv_free_ char **strv = NULL;
         char *val1, *val2, *val3, *val4;
 
         val1 = strdup("val1");
@@ -109,7 +109,7 @@ TEST(hashmap_get_strv) {
 }
 
 TEST(hashmap_move_one) {
-        _cleanup_(hashmap_free_freep) Hashmap *m = NULL, *n = NULL;
+        _cleanup_hashmap_free_free_ Hashmap *m = NULL, *n = NULL;
         char *val1, *val2, *val3, *val4, *r;
 
         val1 = strdup("val1");
@@ -145,7 +145,7 @@ TEST(hashmap_move_one) {
 }
 
 TEST(hashmap_move) {
-        _cleanup_(hashmap_free_freep) Hashmap *m = NULL, *n = NULL;
+        _cleanup_hashmap_free_free_ Hashmap *m = NULL, *n = NULL;
         char *val1, *val2, *val3, *val4, *r;
 
         val1 = strdup("val1");
@@ -184,7 +184,7 @@ TEST(hashmap_move) {
 }
 
 TEST(hashmap_update) {
-        _cleanup_(hashmap_freep) Hashmap *m = NULL;
+        _cleanup_hashmap_free_ Hashmap *m = NULL;
         _cleanup_free_ char *val1 = NULL, *val2 = NULL;
         char *r;
 
@@ -208,7 +208,7 @@ TEST(hashmap_update) {
 }
 
 TEST(hashmap_put) {
-        _cleanup_(hashmap_freep) Hashmap *m = NULL;
+        _cleanup_hashmap_free_ Hashmap *m = NULL;
         int valid_hashmap_put;
         void *val1 = (void*) "val 1";
         void *val2 = (void*) "val 2";
@@ -417,7 +417,7 @@ TEST(hashmap_ensure_allocated) {
 }
 
 TEST(hashmap_foreach_key) {
-        _cleanup_(hashmap_freep) Hashmap *m = NULL;
+        _cleanup_hashmap_free_ Hashmap *m = NULL;
         bool key_found[] = { false, false, false, false };
         const char *s;
         const char *key;
@@ -449,7 +449,7 @@ TEST(hashmap_foreach_key) {
 }
 
 TEST(hashmap_foreach) {
-        _cleanup_(hashmap_free_freep) Hashmap *m = NULL;
+        _cleanup_hashmap_free_free_ Hashmap *m = NULL;
         bool value_found[] = { false, false, false, false };
         char *val1, *val2, *val3, *val4, *s;
         unsigned count;
@@ -496,8 +496,8 @@ TEST(hashmap_foreach) {
 }
 
 TEST(hashmap_merge) {
-        _cleanup_(hashmap_free_freep) Hashmap *m = NULL;
-        _cleanup_(hashmap_freep) Hashmap *n = NULL;
+        _cleanup_hashmap_free_free_ Hashmap *m = NULL;
+        _cleanup_hashmap_free_ Hashmap *n = NULL;
         char *val1, *val2, *val3, *val4, *r;
 
         val1 = strdup("my val1");
@@ -528,7 +528,7 @@ TEST(hashmap_merge) {
 }
 
 TEST(hashmap_contains) {
-        _cleanup_(hashmap_free_freep) Hashmap *m = NULL;
+        _cleanup_hashmap_free_free_ Hashmap *m = NULL;
         char *val1;
 
         val1 = strdup("my val");
@@ -547,7 +547,7 @@ TEST(hashmap_contains) {
 }
 
 TEST(hashmap_isempty) {
-        _cleanup_(hashmap_free_freep) Hashmap *m = NULL;
+        _cleanup_hashmap_free_free_ Hashmap *m = NULL;
         char *val1;
 
         val1 = strdup("my val");
@@ -563,7 +563,7 @@ TEST(hashmap_isempty) {
 }
 
 TEST(hashmap_size) {
-        _cleanup_(hashmap_free_freep) Hashmap *m = NULL;
+        _cleanup_hashmap_free_free_ Hashmap *m = NULL;
         char *val1, *val2, *val3, *val4;
 
         val1 = strdup("my val");
@@ -591,7 +591,7 @@ TEST(hashmap_size) {
 }
 
 TEST(hashmap_get) {
-        _cleanup_(hashmap_free_freep) Hashmap *m = NULL;
+        _cleanup_hashmap_free_free_ Hashmap *m = NULL;
         char *r;
         char *val;
 

src/test/test-install-root.c

@@ -578,7 +578,7 @@ TEST(preset_and_list) {
         UnitFileState state;
         bool got_yes = false, got_no = false;
         UnitFileList *fl;
-        _cleanup_(hashmap_freep) Hashmap *h = NULL;
+        _cleanup_hashmap_free_ Hashmap *h = NULL;
 
         CLEANUP_ARRAY(changes, n_changes, install_changes_free);
 

src/test/test-install.c

@@ -20,7 +20,7 @@ static void dump_changes(InstallChange *c, unsigned n) {
 }
 
 int main(int argc, char* argv[]) {
-        _cleanup_(hashmap_freep) Hashmap *h = NULL;
+        _cleanup_hashmap_free_ Hashmap *h = NULL;
         UnitFileList *p;
         int r;
         const char *const files[] = { "avahi-daemon.service", NULL };

src/test/test-load-fragment.c

@@ -41,7 +41,7 @@ STATIC_DESTRUCTOR_REGISTER(runtime_dir, rm_rf_physical_and_freep);
 
 TEST_RET(unit_file_get_set) {
         int r;
-        _cleanup_(hashmap_freep) Hashmap *h = NULL;
+        _cleanup_hashmap_free_ Hashmap *h = NULL;
         UnitFileList *p;
 
         h = hashmap_new(&unit_file_list_hash_ops_free);

src/test/test-loop-block.c

@@ -143,7 +143,7 @@ static int run(int argc, char *argv[]) {
         sd_id128_t id;
 #endif
         _cleanup_free_ char *p = NULL, *cmd = NULL;
-        _cleanup_(pclosep) FILE *sfdisk = NULL;
+        _cleanup_pclose_ FILE *sfdisk = NULL;
         _cleanup_(loop_device_unrefp) LoopDevice *loop = NULL;
         _cleanup_close_ int fd = -EBADF;
         int r;

src/test/test-memstream-util.c

@@ -0,0 +1,60 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include "memstream-util.h"
+#include "string-util.h"
+#include "tests.h"
+
+TEST(memstream_done) {
+        _cleanup_(memstream_done) MemStream m = {};
+
+        assert_se(memstream_init(&m));
+}
+
+TEST(memstream_empty) {
+        _cleanup_(memstream_done) MemStream m = {};
+        _cleanup_free_ char *buf = NULL;
+        size_t sz;
+
+        assert_se(memstream_init(&m));
+        assert_se(memstream_finalize(&m, &buf, &sz) >= 0);
+        assert_se(streq(buf, ""));
+        assert_se(sz == 0);
+}
+
+TEST(memstream) {
+        _cleanup_(memstream_done) MemStream m = {};
+        _cleanup_free_ char *buf = NULL;
+        size_t sz;
+        FILE *f;
+
+        assert_se(f = memstream_init(&m));
+        fputs("hoge", f);
+        fputs("おはよう！", f);
+        fputs(u8"😀😀😀", f);
+        assert_se(memstream_finalize(&m, &buf, &sz) >= 0);
+        assert_se(streq(buf, u8"hogeおはよう！😀😀😀"));
+        assert_se(sz == strlen(u8"hogeおはよう！😀😀😀"));
+
+        buf = mfree(buf);
+
+        assert_se(f = memstream_init(&m));
+        fputs("second", f);
+        assert_se(memstream_finalize(&m, &buf, &sz) >= 0);
+        assert_se(streq(buf, "second"));
+        assert_se(sz == strlen("second"));
+}
+
+TEST(memstream_dump) {
+        _cleanup_(memstream_done) MemStream m = {};
+        FILE *f;
+
+        assert_se(f = memstream_init(&m));
+        fputs("first", f);
+        assert_se(memstream_dump(LOG_DEBUG, &m) >= 0);
+
+        assert_se(f = memstream_init(&m));
+        fputs("second", f);
+        assert_se(memstream_dump(LOG_DEBUG, &m) >= 0);
+}
+
+DEFINE_TEST_MAIN(LOG_DEBUG);

src/test/test-set.c

@@ -145,8 +145,8 @@ TEST(set_ensure_allocated) {
 }
 
 TEST(set_copy) {
-        _cleanup_(set_freep) Set *s = NULL;
-        _cleanup_(set_free_freep) Set *copy = NULL;
+        _cleanup_set_free_ Set *s = NULL;
+        _cleanup_set_free_free_ Set *copy = NULL;
         char *key1, *key2, *key3, *key4;
 
         key1 = strdup("key1");

src/test/test-strv.c

@@ -260,7 +260,7 @@ TEST(invalid_unquote) {
 }
 
 TEST(strv_split) {
-        _cleanup_(strv_free_erasep) char **l = NULL;
+        _cleanup_strv_free_erase_ char **l = NULL;
         const char str[] = "one,two,three";
 
         l = strv_split(str, ",");

src/test/test-varlink.c

@@ -272,7 +272,7 @@ int main(int argc, char *argv[]) {
         _cleanup_(rm_rf_physical_and_freep) char *tmpdir = NULL;
         _cleanup_(json_variant_unrefp) JsonVariant *v = NULL;
         _cleanup_(sd_event_unrefp) sd_event *e = NULL;
-        _cleanup_(close_pairp) int block_fds[2] = PIPE_EBADF;
+        _cleanup_close_pair_ int block_fds[2] = PIPE_EBADF;
         pthread_t t;
         const char *sp;
 

src/tmpfiles/offline-passwd.c

@@ -35,7 +35,7 @@ static int open_passwd_file(const char *root, const char *fname, FILE **ret_file
 }
 
 static int populate_uid_cache(const char *root, Hashmap **ret) {
-        _cleanup_(hashmap_freep) Hashmap *cache = NULL;
+        _cleanup_hashmap_free_ Hashmap *cache = NULL;
         int r;
 
         cache = hashmap_new(&uid_gid_hash_ops);
@@ -76,7 +76,7 @@ static int populate_uid_cache(const char *root, Hashmap **ret) {
 }
 
 static int populate_gid_cache(const char *root, Hashmap **ret) {
-        _cleanup_(hashmap_freep) Hashmap *cache = NULL;
+        _cleanup_hashmap_free_ Hashmap *cache = NULL;
         int r;
 
         cache = hashmap_new(&uid_gid_hash_ops);

src/tmpfiles/test-offline-passwd.c

@@ -17,7 +17,7 @@ static void test_resolve_one(const char *name) {
 
         log_info("/* %s(\"%s\") */", __func__, name);
 
-        _cleanup_(hashmap_freep) Hashmap *uid_cache = NULL, *gid_cache = NULL;
+        _cleanup_hashmap_free_ Hashmap *uid_cache = NULL, *gid_cache = NULL;
         uid_t uid = UID_INVALID;
         gid_t gid = GID_INVALID;
         int r;

src/tmpfiles/tmpfiles.c

@@ -4055,7 +4055,7 @@ static int read_config_file(
                 bool ignore_enoent,
                 bool *invalid_config) {
 
-        _cleanup_(hashmap_freep) Hashmap *uid_cache = NULL, *gid_cache = NULL;
+        _cleanup_hashmap_free_ Hashmap *uid_cache = NULL, *gid_cache = NULL;
         _cleanup_fclose_ FILE *_f = NULL;
         _cleanup_free_ char *pp = NULL;
         unsigned v = 0;

src/udev/udevadm-lock.c

@@ -287,7 +287,7 @@ static int lock_device(
 }
 
 int lock_main(int argc, char *argv[], void *userdata) {
-        _cleanup_(fdset_freep) FDSet *fds = NULL;
+        _cleanup_fdset_free_ FDSet *fds = NULL;
         _cleanup_free_ dev_t *devnos = NULL;
         size_t n_devnos = 0;
         usec_t deadline;

src/userdb/userdbctl.c

@@ -910,7 +910,7 @@ static int display_memberships(int argc, char *argv[], void *userdata) {
 
 static int display_services(int argc, char *argv[], void *userdata) {
         _cleanup_(table_unrefp) Table *t = NULL;
-        _cleanup_(closedirp) DIR *d = NULL;
+        _cleanup_closedir_ DIR *d = NULL;
         int r;
 
         d = opendir("/run/systemd/userdb/");

src/xdg-autostart-generator/xdg-autostart-generator.c

@@ -95,7 +95,7 @@ static int enumerate_xdg_autostart(Hashmap *all_services) {
 }
 
 static int run(const char *dest, const char *dest_early, const char *dest_late) {
-        _cleanup_(hashmap_freep) Hashmap *all_services = NULL;
+        _cleanup_hashmap_free_ Hashmap *all_services = NULL;
         XdgAutostartService *service;
         int r;