pidof/killall: allow find_pid_by_name to find running

 processes started as scripts_with_name_longer_than_15_bytes.sh
 closes bug 4054 (and is generally neat)

2 files changed, 42 insertions, 18 deletions

diff --git a/libbb/find_pid_by_name.c b/libbb/find_pid_by_name.c
index ae2f11643..2ee423cb7 100644
--- a/libbb/find_pid_by_name.c
+++ b/libbb/find_pid_by_name.c
@@ -38,6 +38,35 @@ execXXX("/proc/self/exe", applet_name, params....)
 and therefore comm field contains "exe".
 */
 
+static int comm_match(procps_status_t *p, const char *procName)
+{
+        int argv1idx;
+
+        /* comm does not match */
+        if (strncmp(p->comm, procName, 15) != 0)
+                return 0;
+
+        /* in Linux, if comm is 15 chars, it may be a truncated */
+        if (p->comm[14] == '\0') /* comm is not truncated - match */
+                return 1;
+
+        /* comm is truncated, but first 15 chars match.
+         * This can be crazily_long_script_name.sh!
+         * The telltale sign is basename(argv[1]) == procName. */
+
+        if (!p->argv0)
+                return 0;
+
+        argv1idx = strlen(p->argv0) + 1;
+        if (argv1idx >= p->argv_len)
+                return 0;
+
+        if (strcmp(bb_basename(p->argv0 + argv1idx), procName) != 0)
+                return 0;
+
+        return 1;
+}
+
 /* find_pid_by_name()
  *
  *  Modified by Vladimir Oleynik for use with libbb/procps.c
@@ -48,24 +77,20 @@ and therefore comm field contains "exe".
  *  Returns a list of all matching PIDs
  *  It is the caller's duty to free the returned pidlist.
  */
-pid_t* FAST_FUNC find_pid_by_name(const char* procName)
+pid_t* FAST_FUNC find_pid_by_name(const char *procName)
 {
         pid_t* pidList;
         int i = 0;
         procps_status_t* p = NULL;
 
-        pidList = xmalloc(sizeof(*pidList));
-        while ((p = procps_scan(p, PSSCAN_PID|PSSCAN_COMM|PSSCAN_ARGV0))) {
-                if (
-                /* we require comm to match and to not be truncated */
-                /* in Linux, if comm is 15 chars, it may be a truncated
-                 * name, so we don't allow that to match */
-                    (!p->comm[sizeof(p->comm)-2] && strcmp(p->comm, procName) == 0)
+        pidList = xzalloc(sizeof(*pidList));
+        while ((p = procps_scan(p, PSSCAN_PID|PSSCAN_COMM|PSSCAN_ARGVN))) {
+                if (comm_match(p, procName)
                 /* or we require argv0 to match (essential for matching reexeced /proc/self/exe)*/
                  || (p->argv0 && strcmp(bb_basename(p->argv0), procName) == 0)
                 /* TOOD: we can also try /proc/NUM/exe link, do we want that? */
                 ) {
-                        pidList = xrealloc(pidList, sizeof(*pidList) * (i+2));
+                        pidList = xrealloc_vector(pidList, 2, i);
                         pidList[i++] = p->pid;
                 }
         }
diff --git a/libbb/procps.c b/libbb/procps.c
index a5168a077..f799099fd 100644
--- a/libbb/procps.c
+++ b/libbb/procps.c
@@ -78,7 +78,7 @@ const char* FAST_FUNC get_cached_groupname(gid_t gid)
 
 #define PROCPS_BUFSIZE 1024
 
-static int FAST_FUNC read_to_buf(const char *filename, void *buf)
+static int read_to_buf(const char *filename, void *buf)
 {
         int fd;
         /* open_read_close() would do two reads, checking for EOF.
@@ -385,16 +385,15 @@ procps_status_t* FAST_FUNC procps_scan(procps_status_t* sp, int flags)
                         n = read_to_buf(filename, buf);
                         if (n <= 0)
                                 break;
-#if ENABLE_PGREP || ENABLE_PKILL
                         if (flags & PSSCAN_ARGVN) {
-                                do {
-                                        n--;
-                                        if (buf[n] == '\0')
-                                                buf[n] = ' ';
-                                } while (n);
+                                sp->argv_len = n;
+                                sp->argv0 = xmalloc(n + 1);
+                                memcpy(sp->argv0, buf, n + 1);
+                                /* sp->argv0[n] = '\0'; - buf has it */
+                        } else {
+                                sp->argv_len = 0;
+                                sp->argv0 = xstrdup(buf);
                         }
-#endif
-                        sp->argv0 = xstrdup(buf);
                 }
 #endif
                 break;