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authorLennart Poettering <lennart@poettering.net>2013-04-16 14:50:05 +0200
committerLennart Poettering <lennart@poettering.net>2013-04-16 14:50:05 +0200
commit49aa47c7fb6c6cf85f2780080e89181974efdc3b (patch)
tree6d0af790210faa80b0cf4d9d565be0d3d629eb51 /src/shared/util.c
parent6606089752df90f3eeb4924af109046f1c73554c (diff)
util: make generation of profcs PID paths nicer
Diffstat (limited to 'src/shared/util.c')
-rw-r--r--src/shared/util.c169
1 files changed, 87 insertions, 82 deletions
diff --git a/src/shared/util.c b/src/shared/util.c
index 53caa7f9e5..a55b27f878 100644
--- a/src/shared/util.c
+++ b/src/shared/util.c
@@ -80,15 +80,14 @@ char **saved_argv = NULL;
static volatile unsigned cached_columns = 0;
static volatile unsigned cached_lines = 0;
-#define PROCFS_PATH_LEN (sizeof("/proc/")-1 + DECIMAL_STR_MAX(pid_t))
-
-#define FORMAT_PROCFS_PATH(buffer, path, pid) \
- do { \
- assert_cc(sizeof(buffer) == (PROCFS_PATH_LEN + 1 + sizeof(path))); \
- snprintf(buffer, sizeof(buffer) - 1, "/proc/%lu/%s", (unsigned long) pid, path); \
- char_array_0(buffer); \
- } while(0)
-
+#define procfs_file_alloca(pid, field) \
+ ({ \
+ pid_t _pid_ = (pid); \
+ char *_r_; \
+ _r_ = alloca(sizeof("/proc/") -1 + DECIMAL_STR_MAX(pid_t) + 1 + sizeof(field)); \
+ sprintf(_r_, "/proc/%lu/" field, (unsigned long) _pid_); \
+ _r_; \
+ })
size_t page_size(void) {
static __thread size_t pgsz = 0;
@@ -468,15 +467,20 @@ 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[sizeof("/proc/")-1 + DECIMAL_STR_MAX(pid_t) + sizeof("/stat")], line[LINE_MAX], *p;
+ char line[LINE_MAX];
long unsigned ppid;
+ const char *p;
- assert(pid > 0);
+ assert(pid >= 0);
assert(_ppid);
- assert_se(snprintf(fn, sizeof(fn)-1, "/proc/%lu/stat", (unsigned long) pid) < (int) (sizeof(fn)-1));
+ if (pid == 0) {
+ *_ppid = getppid();
+ return 0;
+ }
- f = fopen(fn, "re");
+ p = procfs_file_alloca(pid, "stat");
+ f = fopen(p, "re");
if (!f)
return -errno;
@@ -511,14 +515,18 @@ 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[sizeof("/proc/")-1 + DECIMAL_STR_MAX(pid_t) + sizeof("/stat")], line[LINE_MAX], *p;
+ char line[LINE_MAX];
+ const char *p;
- assert(pid > 0);
+ assert(pid >= 0);
assert(st);
- assert_se(snprintf(fn, sizeof(fn)-1, "/proc/%lu/stat", (unsigned long) pid) < (int) (sizeof(fn)-1));
+ if (pid == 0)
+ p = "/proc/self/stat";
+ else
+ p = procfs_file_alloca(pid, "stat");
- f = fopen(fn, "re");
+ f = fopen(p, "re");
if (!f)
return -errno;
@@ -585,60 +593,60 @@ char *truncate_nl(char *s) {
}
int get_process_comm(pid_t pid, char **name) {
- int r;
+ const char *p;
assert(name);
+ assert(pid >= 0);
if (pid == 0)
- r = read_one_line_file("/proc/self/comm", name);
- else {
- char path[PROCFS_PATH_LEN + sizeof("/comm")];
- FORMAT_PROCFS_PATH(path, "comm", pid);
- r = read_one_line_file(path, name);
- }
+ p = "/proc/self/comm";
+ else
+ p = procfs_file_alloca(pid, "comm");
- return r;
+ return read_one_line_file(p, name);
}
int get_process_cmdline(pid_t pid, size_t max_length, bool comm_fallback, char **line) {
+ _cleanup_fclose_ FILE *f = NULL;
char *r = NULL, *k;
+ const char *p;
int c;
- FILE *f;
assert(line);
+ assert(pid >= 0);
if (pid == 0)
- f = fopen("/proc/self/cmdline", "re");
- else {
- char path[PROCFS_PATH_LEN + sizeof("/cmdline")];
- FORMAT_PROCFS_PATH(path, "cmdline", pid);
- f = fopen(path, "re");
- }
+ p = "/proc/self/cmdline";
+ else
+ p = procfs_file_alloca(pid, "cmdline");
+ f = fopen(p, "re");
if (!f)
return -errno;
+
if (max_length == 0) {
- size_t len = 1;
+ size_t len = 0, allocated = 0;
+
while ((c = getc(f)) != EOF) {
- k = realloc(r, len+1);
- if (k == NULL) {
+
+ if (!GREEDY_REALLOC(r, allocated, len+2)) {
free(r);
- fclose(f);
return -ENOMEM;
}
- r = k;
- r[len-1] = isprint(c) ? c : ' ';
- r[len] = 0;
- len++;
+
+ r[len++] = isprint(c) ? c : ' ';
}
+
+ if (len > 0)
+ r[len-1] = 0;
+
} else {
bool space = false;
size_t left;
+
r = new(char, max_length);
- if (!r) {
- fclose(f);
+ if (!r)
return -ENOMEM;
- }
k = r;
left = max_length;
@@ -671,8 +679,6 @@ int get_process_cmdline(pid_t pid, size_t max_length, bool comm_fallback, char *
*k = 0;
}
- fclose(f);
-
/* Kernel threads have no argv[] */
if (r == NULL || r[0] == 0) {
char *t;
@@ -699,7 +705,7 @@ int get_process_cmdline(pid_t pid, size_t max_length, bool comm_fallback, char *
}
int is_kernel_thread(pid_t pid) {
- char path[PROCFS_PATH_LEN + sizeof("/cmdline")];
+ const char *p;
size_t count;
char c;
bool eof;
@@ -708,9 +714,10 @@ int is_kernel_thread(pid_t pid) {
if (pid == 0)
return 0;
- FORMAT_PROCFS_PATH(path, "cmdline", pid);
- f = fopen(path, "re");
+ assert(pid > 0);
+ p = procfs_file_alloca(pid, "cmdline");
+ f = fopen(p, "re");
if (!f)
return -errno;
@@ -726,26 +733,25 @@ int is_kernel_thread(pid_t pid) {
return 0;
}
+
int get_process_exe(pid_t pid, char **name) {
- int r;
+ const char *p;
+ assert(pid >= 0);
assert(name);
if (pid == 0)
- r = readlink_malloc("/proc/self/exe", name);
- else {
- char path[PROCFS_PATH_LEN + sizeof("/exe")];
- FORMAT_PROCFS_PATH(path, "exe", pid);
- r = readlink_malloc(path, name);
- }
+ p = "/proc/self/exe";
+ else
+ p = procfs_file_alloca(pid, "exe");
- return r;
+ return readlink_malloc(p, name);
}
static int get_process_id(pid_t pid, const char *field, uid_t *uid) {
_cleanup_fclose_ FILE *f = NULL;
- char path[PROCFS_PATH_LEN + sizeof("/status")];
char line[LINE_MAX];
+ const char *p;
assert(field);
assert(uid);
@@ -753,8 +759,8 @@ static int get_process_id(pid_t pid, const char *field, uid_t *uid) {
if (pid == 0)
return getuid();
- FORMAT_PROCFS_PATH(path, "status", pid);
- f = fopen(path, "re");
+ p = procfs_file_alloca(pid, "status");
+ f = fopen(p, "re");
if (!f)
return -errno;
@@ -781,6 +787,7 @@ int get_process_uid(pid_t pid, uid_t *uid) {
}
int get_process_gid(pid_t pid, gid_t *gid) {
+ assert_cc(sizeof(uid_t) == sizeof(gid_t));
return get_process_id(pid, "Gid:", gid);
}
@@ -2566,27 +2573,29 @@ int getttyname_harder(int fd, char **r) {
}
int get_ctty_devnr(pid_t pid, dev_t *d) {
- int k;
- char line[LINE_MAX], *p, *fn;
+ _cleanup_fclose_ FILE *f = NULL;
+ char line[LINE_MAX], *p;
unsigned long ttynr;
- FILE *f;
+ const char *fn;
+ int k;
- if (asprintf(&fn, "/proc/%lu/stat", (unsigned long) (pid <= 0 ? getpid() : pid)) < 0)
- return -ENOMEM;
+ assert(pid >= 0);
+ assert(d);
+
+ if (pid == 0)
+ fn = "/proc/self/stat";
+ else
+ fn = procfs_file_alloca(pid, "stat");
f = fopen(fn, "re");
- free(fn);
if (!f)
return -errno;
if (!fgets(line, sizeof(line), f)) {
k = feof(f) ? -EIO : -errno;
- fclose(f);
return k;
}
- fclose(f);
-
p = strrchr(line, ')');
if (!p)
return -EIO;
@@ -5031,19 +5040,21 @@ 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 + DECIMAL_STR_MAX(pid_t) + sizeof("/environ")], *value = NULL;
+ _cleanup_fclose_ FILE *f = NULL;
+ char *value = NULL;
int r;
- FILE *f;
bool done = false;
size_t l;
+ const char *path;
+ assert(pid >= 0);
assert(field);
assert(_value);
if (pid == 0)
- pid = getpid();
-
- snprintf(path, sizeof(path), "/proc/%lu/environ", (unsigned long) pid);
+ path = "/proc/self/environ";
+ else
+ path = procfs_file_alloca(pid, "environ");
f = fopen(path, "re");
if (!f)
@@ -5072,10 +5083,8 @@ int getenv_for_pid(pid_t pid, const char *field, char **_value) {
if (memcmp(line, field, l) == 0 && line[l] == '=') {
value = strdup(line + l + 1);
- if (!value) {
- r = -ENOMEM;
- break;
- }
+ if (!value)
+ return -ENOMEM;
r = 1;
break;
@@ -5083,11 +5092,7 @@ int getenv_for_pid(pid_t pid, const char *field, char **_value) {
} while (!done);
- fclose(f);
-
- if (r >= 0)
- *_value = value;
-
+ *_value = value;
return r;
}