diff options
Diffstat (limited to 'src/basic/process-util.c')
| -rw-r--r-- | src/basic/process-util.c | 90 |
1 files changed, 79 insertions, 11 deletions
diff --git a/src/basic/process-util.c b/src/basic/process-util.c index 08fa98bb9e..b5b068ad38 100644 --- a/src/basic/process-util.c +++ b/src/basic/process-util.c @@ -110,6 +110,15 @@ int get_process_cmdline(pid_t pid, size_t max_length, bool comm_fallback, char * assert(line); assert(pid >= 0); + /* Retrieves a process' command line. Replaces unprintable characters while doing so by whitespace (coalescing + * multiple sequential ones into one). If max_length is != 0 will return a string of the specified size at most + * (the trailing NUL byte does count towards the length here!), abbreviated with a "..." ellipsis. If + * comm_fallback is true and the process has no command line set (the case for kernel threads), or has a + * command line that resolves to the empty string will return the "comm" name of the process instead. + * + * Returns -ESRCH if the process doesn't exist, and -ENOENT if the process has no command line (and + * comm_fallback is false). */ + p = procfs_file_alloca(pid, "cmdline"); f = fopen(p, "re"); @@ -119,12 +128,22 @@ int get_process_cmdline(pid_t pid, size_t max_length, bool comm_fallback, char * return -errno; } - if (max_length == 0) { + if (max_length == 1) { + + /* If there's only room for one byte, return the empty string */ + r = new0(char, 1); + if (!r) + return -ENOMEM; + + *line = r; + return 0; + + } else if (max_length == 0) { size_t len = 0, allocated = 0; while ((c = getc(f)) != EOF) { - if (!GREEDY_REALLOC(r, allocated, len+2)) { + if (!GREEDY_REALLOC(r, allocated, len+3)) { free(r); return -ENOMEM; } @@ -136,7 +155,7 @@ int get_process_cmdline(pid_t pid, size_t max_length, bool comm_fallback, char * } r[len++] = c; - } else + } else if (len > 0) space = true; } @@ -144,6 +163,7 @@ int get_process_cmdline(pid_t pid, size_t max_length, bool comm_fallback, char * r[len] = 0; } else { + bool dotdotdot = false; size_t left; r = new(char, max_length); @@ -155,28 +175,46 @@ int get_process_cmdline(pid_t pid, size_t max_length, bool comm_fallback, char * while ((c = getc(f)) != EOF) { if (isprint(c)) { + if (space) { - if (left <= 4) + if (left <= 2) { + dotdotdot = true; break; + } *(k++) = ' '; left--; space = false; } - if (left <= 4) + if (left <= 1) { + dotdotdot = true; break; + } *(k++) = (char) c; left--; - } else + } else if (k > r) space = true; } - if (left <= 4) { - size_t n = MIN(left-1, 3U); - memcpy(k, "...", n); - k[n] = 0; + if (dotdotdot) { + if (max_length <= 4) { + k = r; + left = max_length; + } else { + k = r + max_length - 4; + left = 4; + + /* Eat up final spaces */ + while (k > r && isspace(k[-1])) { + k--; + left++; + } + } + + strncpy(k, "...", left-1); + k[left] = 0; } else *k = 0; } @@ -195,7 +233,37 @@ int get_process_cmdline(pid_t pid, size_t max_length, bool comm_fallback, char * if (h < 0) return h; - r = strjoin("[", t, "]", NULL); + if (max_length == 0) + r = strjoin("[", t, "]", NULL); + else { + size_t l; + + l = strlen(t); + + if (l + 3 <= max_length) + r = strjoin("[", t, "]", NULL); + else if (max_length <= 6) { + + r = new(char, max_length); + if (!r) + return -ENOMEM; + + memcpy(r, "[...]", max_length-1); + r[max_length-1] = 0; + } else { + char *e; + + t[max_length - 6] = 0; + + /* Chop off final spaces */ + e = strchr(t, 0); + while (e > t && isspace(e[-1])) + e--; + *e = 0; + + r = strjoin("[", t, "...]", NULL); + } + } if (!r) return -ENOMEM; } |