diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/shared/util.c | 135 | ||||
| -rw-r--r-- | src/shared/util.h | 21 |
2 files changed, 156 insertions, 0 deletions
diff --git a/src/shared/util.c b/src/shared/util.c index 9721779b4b..0a9696f424 100644 --- a/src/shared/util.c +++ b/src/shared/util.c @@ -427,6 +427,115 @@ int rmdir_parents(const char *path, const char *stop) { return 0; } +int get_process_comm(pid_t pid, char **name) { + const char *p; + int r; + + assert(name); + assert(pid >= 0); + + p = procfs_file_alloca(pid, "comm"); + + r = read_one_line_file(p, name); + if (r == -ENOENT) + return -ESRCH; + + return r; +} + +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; + + assert(line); + assert(pid >= 0); + + p = procfs_file_alloca(pid, "cmdline"); + + f = fopen(p, "re"); + if (!f) + return -errno; + + if (max_length == 0) { + size_t len = 0, allocated = 0; + + while ((c = getc(f)) != EOF) { + + if (!GREEDY_REALLOC(r, allocated, len+2)) { + free(r); + return -ENOMEM; + } + + 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) + return -ENOMEM; + + k = r; + left = max_length; + while ((c = getc(f)) != EOF) { + + if (isprint(c)) { + if (space) { + if (left <= 4) + break; + + *(k++) = ' '; + left--; + space = false; + } + + if (left <= 4) + break; + + *(k++) = (char) c; + left--; + } else + space = true; + } + + if (left <= 4) { + size_t n = MIN(left-1, 3U); + memcpy(k, "...", n); + k[n] = 0; + } else + *k = 0; + } + + /* Kernel threads have no argv[] */ + if (isempty(r)) { + _cleanup_free_ char *t = NULL; + int h; + + free(r); + + if (!comm_fallback) + return -ENOENT; + + h = get_process_comm(pid, &t); + if (h < 0) + return h; + + r = strjoin("[", t, "]", NULL); + if (!r) + return -ENOMEM; + } + + *line = r; + return 0; +} + char hexchar(int x) { static const char table[16] = "0123456789abcdef"; @@ -1317,6 +1426,32 @@ void *xbsearch_r(const void *key, const void *base, size_t nmemb, size_t size, return NULL; } +void* greedy_realloc(void **p, size_t *allocated, size_t need, size_t size) { + size_t a, newalloc; + void *q; + + assert(p); + assert(allocated); + + if (*allocated >= need) + return *p; + + newalloc = MAX(need * 2, 64u / size); + a = newalloc * size; + + /* check for overflows */ + if (a < size * need) + return NULL; + + q = realloc(*p, a); + if (!q) + return NULL; + + *p = q; + *allocated = newalloc; + return q; +} + int proc_cmdline(char **ret) { assert(ret); diff --git a/src/shared/util.h b/src/shared/util.h index a25b2f5aec..ebb02a66b9 100644 --- a/src/shared/util.h +++ b/src/shared/util.h @@ -180,6 +180,10 @@ char *strnappend(const char *s, const char *suffix, size_t length); char *truncate_nl(char *s); int rmdir_parents(const char *path, const char *stop); + +int get_process_comm(pid_t pid, char **name); +int get_process_cmdline(pid_t pid, size_t max_length, bool comm_fallback, char **line); + char hexchar(int x) _const_; char octchar(int x) _const_; @@ -374,6 +378,10 @@ static inline void *mempset(void *s, int c, size_t n) { return (uint8_t*)s + n; } + +void* greedy_realloc(void **p, size_t *allocated, size_t need, size_t size); +#define GREEDY_REALLOC(array, allocated, need) \ + greedy_realloc((void**) &(array), &(allocated), (need), sizeof((array)[0])) static inline void _reset_errno_(int *saved_errno) { errno = *saved_errno; } @@ -412,6 +420,19 @@ int unlink_noerrno(const char *path); _d_; \ }) +#define procfs_file_alloca(pid, field) \ + ({ \ + pid_t _pid_ = (pid); \ + const char *_r_; \ + if (_pid_ == 0) { \ + _r_ = ("/proc/self/" field); \ + } else { \ + _r_ = alloca(strlen("/proc/") + DECIMAL_STR_MAX(pid_t) + 1 + sizeof(field)); \ + sprintf((char*) _r_, "/proc/"PID_FMT"/" field, _pid_); \ + } \ + _r_; \ + }) + static inline void qsort_safe(void *base, size_t nmemb, size_t size, int (*compar)(const void *, const void *)) { if (nmemb) { |