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Use initalization instead of explicit zeroing

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Before, we would initialize many fields twice: first
by filling the structure with zeros, and then a second
time with the real values. We can let the compiler do
the job for us, avoiding one copy.

A downside of this patch is that text gets slightly
bigger. This is because all zero() calls are effectively
inlined:

$ size build/.libs/systemd
         text    data     bss     dec     hex filename
before 897737  107300    2560 1007597   f5fed build/.libs/systemd
after  897873  107300    2560 1007733   f6075 build/.libs/systemd

… actually less than 1‰.

A few asserts that the parameter is not null had to be removed. I
don't think this changes much, because first, it is quite unlikely
for the assert to fail, and second, an immediate SEGV is almost as
good as an assert.
This commit is contained in:
Zbigniew Jędrzejewski-Szmek
2013-04-05 19:50:57 -04:00
parent 8c62ecf1a9
commit b92bea5d2a
49 changed files with 392 additions and 554 deletions
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src/shared/install.c
+12 -12
View File
@@ -700,7 +700,7 @@ int unit_file_link(
UnitFileChange **changes,
unsigned *n_changes) {
LookupPaths _cleanup_lookup_paths_free_ paths = {NULL};
LookupPaths _cleanup_lookup_paths_free_ paths = {};
char **i;
char _cleanup_free_ *config_path = NULL;
int r, q;
@@ -1116,7 +1116,7 @@ static int unit_file_can_install(
const char *name,
bool allow_symlink) {
InstallContext _cleanup_install_context_done_ c = {NULL};
InstallContext _cleanup_install_context_done_ c = {};
InstallInfo *i;
int r;
@@ -1452,8 +1452,8 @@ int unit_file_enable(
UnitFileChange **changes,
unsigned *n_changes) {
LookupPaths _cleanup_lookup_paths_free_ paths = {NULL};
InstallContext _cleanup_install_context_done_ c = {NULL};
LookupPaths _cleanup_lookup_paths_free_ paths = {};
InstallContext _cleanup_install_context_done_ c = {};
char **i;
char _cleanup_free_ *config_path = NULL;
int r;
@@ -1491,8 +1491,8 @@ int unit_file_disable(
UnitFileChange **changes,
unsigned *n_changes) {
LookupPaths _cleanup_lookup_paths_free_ paths = {NULL};
InstallContext _cleanup_install_context_done_ c = {NULL};
LookupPaths _cleanup_lookup_paths_free_ paths = {};
InstallContext _cleanup_install_context_done_ c = {};
char **i;
char _cleanup_free_ *config_path = NULL;
Set _cleanup_set_free_free_ *remove_symlinks_to = NULL;
@@ -1533,8 +1533,8 @@ int unit_file_reenable(
UnitFileChange **changes,
unsigned *n_changes) {
LookupPaths _cleanup_lookup_paths_free_ paths = {NULL};
InstallContext _cleanup_install_context_done_ c = {NULL};
LookupPaths _cleanup_lookup_paths_free_ paths = {};
InstallContext _cleanup_install_context_done_ c = {};
char **i;
char _cleanup_free_ *config_path = NULL;
Set _cleanup_set_free_free_ *remove_symlinks_to = NULL;
@@ -1576,7 +1576,7 @@ UnitFileState unit_file_get_state(
const char *root_dir,
const char *name) {
LookupPaths _cleanup_lookup_paths_free_ paths = {NULL};
LookupPaths _cleanup_lookup_paths_free_ paths = {};
UnitFileState state = _UNIT_FILE_STATE_INVALID;
char **i;
char _cleanup_free_ *path = NULL;
@@ -1734,8 +1734,8 @@ int unit_file_preset(
UnitFileChange **changes,
unsigned *n_changes) {
LookupPaths _cleanup_lookup_paths_free_ paths = {NULL};
InstallContext _cleanup_install_context_done_ plus = {NULL}, minus = {NULL};
LookupPaths _cleanup_lookup_paths_free_ paths = {};
InstallContext _cleanup_install_context_done_ plus = {}, minus = {NULL};
char **i;
char _cleanup_free_ *config_path = NULL;
Set _cleanup_set_free_free_ *remove_symlinks_to = NULL;
@@ -1800,7 +1800,7 @@ int unit_file_get_list(
const char *root_dir,
Hashmap *h) {
LookupPaths _cleanup_lookup_paths_free_ paths = {NULL};
LookupPaths _cleanup_lookup_paths_free_ paths = {};
char **i;
char _cleanup_free_ *buf = NULL;
DIR _cleanup_closedir_ *d = NULL;