util: add a bit of syntactic sugar to run short code fragments with a different umask

[elogind.git] / src / shared / util.c

diff --git a/src/shared/util.c b/src/shared/util.c
index b516b9b0532e5163593487e7fc7f6a1e41aa5029..1bffd84d1fa71610df46a445f405581241d8d271 100644 (file)
--- a/src/shared/util.c
+++ b/src/shared/util.c
@@ -207,14 +207,12 @@ int close_nointr(int fd) {
 }
 
 void close_nointr_nofail(int fd) {
-        int saved_errno = errno;
+        PROTECT_ERRNO;
 
         /* like close_nointr() but cannot fail, and guarantees errno
          * is unchanged */
 
         assert_se(close_nointr(fd) == 0);
-
-        errno = saved_errno;
 }
 
 void close_many(const int fds[], unsigned n_fd) {
@@ -449,14 +447,13 @@ char *split_quoted(const char *c, size_t *l, char **state) {
 int get_parent_of_pid(pid_t pid, pid_t *_ppid) {
         int r;
         _cleanup_fclose_ FILE *f = NULL;
-        char fn[PATH_MAX], line[LINE_MAX], *p;
+        char fn[sizeof("/proc/")-1 + DECIMAL_STR_MAX(pid_t) + sizeof("/stat")], line[LINE_MAX], *p;
         long unsigned ppid;
 
         assert(pid > 0);
         assert(_ppid);
 
         assert_se(snprintf(fn, sizeof(fn)-1, "/proc/%lu/stat", (unsigned long) pid) < (int) (sizeof(fn)-1));
-        char_array_0(fn);
 
         f = fopen(fn, "re");
         if (!f)
@@ -493,13 +490,12 @@ int get_parent_of_pid(pid_t pid, pid_t *_ppid) {
 
 int get_starttime_of_pid(pid_t pid, unsigned long long *st) {
         _cleanup_fclose_ FILE *f = NULL;
-        char fn[PATH_MAX], line[LINE_MAX], *p;
+        char fn[sizeof("/proc/")-1 + DECIMAL_STR_MAX(pid_t) + sizeof("/stat")], line[LINE_MAX], *p;
 
         assert(pid > 0);
         assert(st);
 
         assert_se(snprintf(fn, sizeof(fn)-1, "/proc/%lu/stat", (unsigned long) pid) < (int) (sizeof(fn)-1));
-        char_array_0(fn);
 
         f = fopen(fn, "re");
         if (!f)
@@ -2613,7 +2609,7 @@ int get_ctty_devnr(pid_t pid, dev_t *d) {
 
 int get_ctty(pid_t pid, dev_t *_devnr, char **r) {
         int k;
-        char fn[PATH_MAX], *s, *b, *p;
+        char fn[sizeof("/dev/char/")-1 + 2*DECIMAL_STR_MAX(unsigned) + 1 + 1], *s, *b, *p;
         dev_t devnr;
 
         assert(r);
@@ -2623,7 +2619,6 @@ int get_ctty(pid_t pid, dev_t *_devnr, char **r) {
                 return k;
 
         snprintf(fn, sizeof(fn), "/dev/char/%u:%u", major(devnr), minor(devnr));
-        char_array_0(fn);
 
         k = readlink_malloc(fn, &s);
         if (k < 0) {
@@ -4764,7 +4759,7 @@ static const char *const __signal_table[] = {
 DEFINE_PRIVATE_STRING_TABLE_LOOKUP(__signal, int);
 
 const char *signal_to_string(int signo) {
-        static __thread char buf[12];
+        static __thread char buf[sizeof("RTMIN+")-1 + DECIMAL_STR_MAX(int) + 1];
         const char *name;
 
         name = __signal_to_string(signo);
@@ -4772,10 +4767,10 @@ const char *signal_to_string(int signo) {
                 return name;
 
         if (signo >= SIGRTMIN && signo <= SIGRTMAX)
-                snprintf(buf, sizeof(buf) - 1, "RTMIN+%d", signo - SIGRTMIN);
+                snprintf(buf, sizeof(buf), "RTMIN+%d", signo - SIGRTMIN);
         else
-                snprintf(buf, sizeof(buf) - 1, "%d", signo);
-        char_array_0(buf);
+                snprintf(buf, sizeof(buf), "%d", signo);
+
         return buf;
 }
 
@@ -5043,7 +5038,7 @@ int setrlimit_closest(int resource, const struct rlimit *rlim) {
 }
 
 int getenv_for_pid(pid_t pid, const char *field, char **_value) {
-        char path[sizeof("/proc/")-1+10+sizeof("/environ")], *value = NULL;
+        char path[sizeof("/proc/")-1 + DECIMAL_STR_MAX(pid_t) + sizeof("/environ")], *value = NULL;
         int r;
         FILE *f;
         bool done = false;
@@ -5056,7 +5051,6 @@ int getenv_for_pid(pid_t pid, const char *field, char **_value) {
                 pid = getpid();
 
         snprintf(path, sizeof(path), "/proc/%lu/environ", (unsigned long) pid);
-        char_array_0(path);
 
         f = fopen(path, "re");
         if (!f)
@@ -5738,12 +5732,12 @@ int search_and_fopen_nulstr(const char *path, const char *mode, const char *sear
 int create_tmp_dir(char template[], char** dir_name) {
         int r = 0;
         char *d, *dt;
-        mode_t _cleanup_umask_ u;
 
         assert(dir_name);
 
-        u = umask(0077);
-        d = mkdtemp(template);
+        RUN_WITH_UMASK(0077) {
+                d = mkdtemp(template);
+        }
         if (!d) {
                 log_error("Can't create directory %s: %m", template);
                 return -errno;
@@ -5755,9 +5749,10 @@ int create_tmp_dir(char template[], char** dir_name) {
                 goto fail3;
         }
 
-        umask(0000);
-        r = mkdir(dt, 0777);
-        if (r) {
+        RUN_WITH_UMASK(0000) {
+                r = mkdir(dt, 0777);
+        }
+        if (r < 0) {
                 log_error("Can't create directory %s: %m", dt);
                 r = -errno;
                 goto fail2;
@@ -5862,7 +5857,7 @@ void* greedy_realloc(void **p, size_t *allocated, size_t need) {
         if (*allocated >= need)
                 return *p;
 
-        a = MAX(64, need * 2);
+        a = MAX(64u, need * 2);
         q = realloc(*p, a);
         if (!q)
                 return NULL;