Use access() instead of stat() when possible

We were using the stat() system call in quite a few places when we didn't
actually need anything the stat struct returned- we were simply checking for
file existence. access() will be more efficient in those cases.

Before (strace pacman -Ss pacman):
% time     seconds  usecs/call     calls    errors syscall
------ ----------- ----------- --------- --------- ----------------
 33.16    0.005987           0     19016           stat64

After:
% time     seconds  usecs/call     calls    errors syscall
------ ----------- ----------- --------- --------- ----------------
 34.85    0.003863           0     12633         1 access
  7.95    0.000881           0      6391         7 stat64

Signed-off-by: Dan McGee <dan@archlinux.org>
This commit is contained in:
Dan McGee 2008-06-15 19:15:36 -05:00
parent 7ff5a917fd
commit 29bf6814f7
6 changed files with 17 additions and 27 deletions

View File

@ -355,7 +355,6 @@ static char *get_pkgpath(pmdb_t *db, pmpkg_t *info)
int _alpm_db_read(pmdb_t *db, pmpkg_t *info, pmdbinfrq_t inforeq)
{
FILE *fp = NULL;
struct stat buf;
char path[PATH_MAX];
char line[513];
char *pkgpath = NULL;
@ -393,7 +392,7 @@ int _alpm_db_read(pmdb_t *db, pmpkg_t *info, pmdbinfrq_t inforeq)
pkgpath = get_pkgpath(db, info);
if(stat(pkgpath, &buf)) {
if(access(pkgpath, F_OK)) {
/* directory doesn't exist or can't be opened */
_alpm_log(PM_LOG_DEBUG, "cannot find '%s-%s' in db '%s'\n",
info->name, info->version, db->treename);
@ -631,7 +630,7 @@ int _alpm_db_read(pmdb_t *db, pmpkg_t *info, pmdbinfrq_t inforeq)
/* INSTALL */
if(inforeq & INFRQ_SCRIPTLET) {
snprintf(path, PATH_MAX, "%sinstall", pkgpath);
if(!stat(path, &buf)) {
if(access(path, F_OK) == 0) {
info->scriptlet = 1;
}
}

View File

@ -25,6 +25,7 @@
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <sys/wait.h>
#include <sys/types.h>
#include <sys/stat.h>
@ -451,7 +452,6 @@ int _alpm_runscriptlet(const char *root, const char *installfn,
char tmpdir[PATH_MAX];
char cwd[PATH_MAX];
char *scriptpath;
struct stat buf;
pid_t pid;
int clean_tmpdir = 0;
int restore_cwd = 0;
@ -459,14 +459,14 @@ int _alpm_runscriptlet(const char *root, const char *installfn,
ALPM_LOG_FUNC;
if(stat(installfn, &buf)) {
if(access(installfn, R_OK)) {
/* not found */
_alpm_log(PM_LOG_DEBUG, "scriptlet '%s' not found\n", installfn);
return(0);
}
/* NOTE: popen will use the PARENT's /bin/sh, not the chroot's */
if(stat("/bin/sh", &buf)) {
if(access("/bin/sh", X_OK)) {
/* not found */
_alpm_log(PM_LOG_ERROR, _("No /bin/sh in parent environment, aborting scriptlet\n"));
return(0);
@ -474,7 +474,7 @@ int _alpm_runscriptlet(const char *root, const char *installfn,
/* creates a directory in $root/tmp/ for copying/extracting the scriptlet */
snprintf(tmpdir, PATH_MAX, "%stmp/", root);
if(stat(tmpdir, &buf)) {
if(access(tmpdir, F_OK) != 0) {
_alpm_makepath_mode(tmpdir, 01777);
}
snprintf(tmpdir, PATH_MAX, "%stmp/alpm_XXXXXX", root);

View File

@ -200,12 +200,11 @@ int _alpm_makepath_mode(const char *path, mode_t mode)
str = orig;
while((ptr = strsep(&str, "/"))) {
if(strlen(ptr)) {
struct stat buf;
/* we have another path component- append the newest component to
* existing string and create one more level of dir structure */
strcat(incr, "/");
strcat(incr, ptr);
if(stat(incr, &buf)) {
if(access(incr, F_OK)) {
if(mkdir(incr, mode)) {
ret = 1;
break;
@ -533,12 +532,11 @@ int _alpm_logaction(unsigned short usesyslog, FILE *f, const char *fmt, va_list
int _alpm_ldconfig(const char *root)
{
char line[PATH_MAX];
struct stat buf;
snprintf(line, PATH_MAX, "%setc/ld.so.conf", root);
if(stat(line, &buf) == 0) {
if(access(line, F_OK) == 0) {
snprintf(line, PATH_MAX, "%ssbin/ldconfig", root);
if(stat(line, &buf) == 0) {
if(access(line, X_OK) == 0) {
char cmd[PATH_MAX];
snprintf(cmd, PATH_MAX, "%s -r %s", line, root);
system(cmd);
@ -561,7 +559,6 @@ int _alpm_str_cmp(const void *s1, const void *s2)
*/
char *_alpm_filecache_find(const char* filename)
{
struct stat buf;
char path[PATH_MAX];
char *retpath;
alpm_list_t *i;
@ -570,8 +567,7 @@ char *_alpm_filecache_find(const char* filename)
for(i = alpm_option_get_cachedirs(); i; i = alpm_list_next(i)) {
snprintf(path, PATH_MAX, "%s%s", (char*)alpm_list_getdata(i),
filename);
if(stat(path, &buf) == 0) {
/* TODO maybe check to make sure it is readable? */
if(access(path, R_OK) == 0) {
retpath = strdup(path);
_alpm_log(PM_LOG_DEBUG, "found cached pkg: %s\n", retpath);
return(retpath);

View File

@ -22,8 +22,8 @@
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <limits.h>
#include <sys/stat.h>
#include <wchar.h>
#include <alpm.h>
@ -176,7 +176,6 @@ void dump_pkg_backups(pmpkg_t *pkg)
if(alpm_pkg_get_backup(pkg)) {
/* package has backup files, so print them */
for(i = alpm_pkg_get_backup(pkg); i; i = alpm_list_next(i)) {
struct stat buf;
char path[PATH_MAX];
char *str = strdup(alpm_list_getdata(i));
char *ptr = index(str, '\t');
@ -188,7 +187,7 @@ void dump_pkg_backups(pmpkg_t *pkg)
ptr++;
snprintf(path, PATH_MAX-1, "%s%s", root, str);
/* if we find the file, calculate checksums, otherwise it is missing */
if(!stat(path, &buf)) {
if(access(path, R_OK) == 0) {
char *md5sum = alpm_get_md5sum(path);
if(md5sum == NULL) {

View File

@ -22,7 +22,6 @@
#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/time.h>
#include <sys/stat.h>
#include <stdio.h>
#include <stdlib.h>
@ -125,7 +124,7 @@ int makepath(const char *path)
* orig - a copy of path so we can safely butcher it with strsep
* str - the current position in the path string (after the delimiter)
* ptr - the original position of str after calling strsep
* incr - incrementally generated path for use in stat/mkdir call
* incr - incrementally generated path for use in access/mkdir call
*/
char *orig, *str, *ptr, *incr;
mode_t oldmask = umask(0000);
@ -136,12 +135,11 @@ int makepath(const char *path)
str = orig;
while((ptr = strsep(&str, "/"))) {
if(strlen(ptr)) {
struct stat buf;
/* we have another path component- append the newest component to
* existing string and create one more level of dir structure */
strcat(incr, "/");
strcat(incr, ptr);
if(stat(incr, &buf)) {
if(access(incr, F_OK)) {
if(mkdir(incr, 0755)) {
ret = 1;
break;

View File

@ -23,7 +23,6 @@
#include <errno.h>
#include <limits.h>
#include <string.h>
#include <sys/stat.h>
#include <dirent.h>
#include <libgen.h>
@ -61,7 +60,6 @@ static int db_test(char *dbpath)
{
struct dirent *ent;
char path[PATH_MAX];
struct stat buf;
int ret = 0;
DIR *dir;
@ -77,17 +75,17 @@ static int db_test(char *dbpath)
}
/* check for desc, depends, and files */
snprintf(path, PATH_MAX, "%s/%s/desc", dbpath, ent->d_name);
if(stat(path, &buf)) {
if(access(path, F_OK)) {
printf("%s: description file is missing\n", ent->d_name);
ret++;
}
snprintf(path, PATH_MAX, "%s/%s/depends", dbpath, ent->d_name);
if(stat(path, &buf)) {
if(access(path, F_OK)) {
printf("%s: dependency file is missing\n", ent->d_name);
ret++;
}
snprintf(path, PATH_MAX, "%s/%s/files", dbpath, ent->d_name);
if(stat(path, &buf)) {
if(access(path, F_OK)) {
printf("%s: file list is missing\n", ent->d_name);
ret++;
}