core: move parsing of rlimits into rlimit-util.[ch]

This way we can reuse it for parsing rlimit settings in "systemctl set-property" and related commands.

src/basic/rlimit-util.c

@@ -22,10 +22,14 @@
 #include <errno.h>
 #include <sys/resource.h>
 
+#include "alloc-util.h"
+#include "extract-word.h"
+#include "formats-util.h"
 #include "macro.h"
 #include "missing.h"
 #include "rlimit-util.h"
 #include "string-table.h"
+#include "time-util.h"
 
 int setrlimit_closest(int resource, const struct rlimit *rlim) {
         struct rlimit highest, fixed;
@@ -51,6 +55,178 @@ int setrlimit_closest(int resource, const struct rlimit *rlim) {
         return 0;
 }
 
+static int rlimit_parse_u64(const char *val, rlim_t *ret) {
+        uint64_t u;
+        int r;
+
+        assert(val);
+        assert(ret);
+
+        if (streq(val, "infinity")) {
+                *ret = RLIM_INFINITY;
+                return 0;
+        }
+
+        /* setrlimit(2) suggests rlim_t is always 64bit on Linux. */
+        assert_cc(sizeof(rlim_t) == sizeof(uint64_t));
+
+        r = safe_atou64(val, &u);
+        if (r < 0)
+                return r;
+        if (u >= (uint64_t) RLIM_INFINITY)
+                return -ERANGE;
+
+        *ret = (rlim_t) u;
+        return 0;
+}
+
+static int rlimit_parse_size(const char *val, rlim_t *ret) {
+        uint64_t u;
+        int r;
+
+        assert(val);
+        assert(ret);
+
+        if (streq(val, "infinity")) {
+                *ret = RLIM_INFINITY;
+                return 0;
+        }
+
+        r = parse_size(val, 1024, &u);
+        if (r < 0)
+                return r;
+        if (u >= (uint64_t) RLIM_INFINITY)
+                return -ERANGE;
+
+        *ret = (rlim_t) u;
+        return 0;
+}
+
+static int rlimit_parse_sec(const char *val, rlim_t *ret) {
+        uint64_t u;
+        usec_t t;
+        int r;
+
+        assert(val);
+        assert(ret);
+
+        if (streq(val, "infinity")) {
+                *ret = RLIM_INFINITY;
+                return 0;
+        }
+
+        r = parse_sec(val, &t);
+        if (r < 0)
+                return r;
+        if (t == USEC_INFINITY) {
+                *ret = RLIM_INFINITY;
+                return 0;
+        }
+
+        u = (uint64_t) DIV_ROUND_UP(t, USEC_PER_SEC);
+        if (u >= (uint64_t) RLIM_INFINITY)
+                return -ERANGE;
+
+        *ret = (rlim_t) u;
+        return 0;
+}
+
+static int rlimit_parse_usec(const char *val, rlim_t *ret) {
+        usec_t t;
+        int r;
+
+        assert(val);
+        assert(ret);
+
+        if (streq(val, "infinity")) {
+                *ret = RLIM_INFINITY;
+                return 0;
+        }
+
+        r = parse_time(val, &t, 1);
+        if (r < 0)
+                return r;
+        if (t == USEC_INFINITY) {
+                *ret = RLIM_INFINITY;
+                return 0;
+        }
+
+        *ret = (rlim_t) t;
+        return 0;
+}
+
+static int (*const rlimit_parse_table[_RLIMIT_MAX])(const char *val, rlim_t *ret) = {
+        [RLIMIT_CPU] = rlimit_parse_sec,
+        [RLIMIT_FSIZE] = rlimit_parse_size,
+        [RLIMIT_DATA] = rlimit_parse_size,
+        [RLIMIT_STACK] = rlimit_parse_size,
+        [RLIMIT_CORE] = rlimit_parse_size,
+        [RLIMIT_RSS] = rlimit_parse_size,
+        [RLIMIT_NOFILE] = rlimit_parse_u64,
+        [RLIMIT_AS] = rlimit_parse_size,
+        [RLIMIT_NPROC] = rlimit_parse_u64,
+        [RLIMIT_MEMLOCK] = rlimit_parse_size,
+        [RLIMIT_LOCKS] = rlimit_parse_u64,
+        [RLIMIT_SIGPENDING] = rlimit_parse_u64,
+        [RLIMIT_MSGQUEUE] = rlimit_parse_size,
+        [RLIMIT_NICE] = rlimit_parse_u64,
+        [RLIMIT_RTPRIO] = rlimit_parse_u64,
+        [RLIMIT_RTTIME] = rlimit_parse_usec,
+};
+
+int rlimit_parse_one(int resource, const char *val, rlim_t *ret) {
+        assert(val);
+        assert(ret);
+
+        if (resource < 0)
+                return -EINVAL;
+        if (resource >= _RLIMIT_MAX)
+                return -EINVAL;
+
+        return rlimit_parse_table[resource](val, ret);
+}
+
+int rlimit_parse(int resource, const char *val, struct rlimit *ret) {
+        _cleanup_free_ char *hard = NULL, *soft = NULL;
+        rlim_t hl, sl;
+        int r;
+
+        assert(val);
+        assert(ret);
+
+        r = extract_first_word(&val, &soft, ":", EXTRACT_DONT_COALESCE_SEPARATORS);
+        if (r < 0)
+                return r;
+        if (r == 0)
+                return -EINVAL;
+
+        r = rlimit_parse_one(resource, soft, &sl);
+        if (r < 0)
+                return r;
+
+        r = extract_first_word(&val, &hard, ":", EXTRACT_DONT_COALESCE_SEPARATORS);
+        if (r < 0)
+                return r;
+        if (!isempty(val))
+                return -EINVAL;
+        if (r == 0)
+                hl = sl;
+        else {
+                r = rlimit_parse_one(resource, hard, &hl);
+                if (r < 0)
+                        return r;
+                if (sl > hl)
+                        return -EILSEQ;
+        }
+
+        *ret = (struct rlimit) {
+                .rlim_cur = sl,
+                .rlim_max = hl,
+        };
+
+        return 0;
+}
+
 static const char* const rlimit_table[_RLIMIT_MAX] = {
         [RLIMIT_CPU] = "LimitCPU",
         [RLIMIT_FSIZE] = "LimitFSIZE",