killbysubdir.c

   1 #define _GNU_SOURCE
   2 #include <stdio.h>
   3 #include <unistd.h>
   4 #include <stdlib.h>
   5 #include <dirent.h>
   6 #include <sys/stat.h>
   7 #include <string.h>
   8 #include <signal.h>
   9 #include <ctype.h>
  10
  11 int main(int argc, char *argv[])
  12 {
  13         char *directory;
  14         DIR *d;
  15         struct dirent *de;
  16         char buf[PATH_MAX];
  17         size_t directory_len;
  18
  19         if (argc < 2) {
  20                 fprintf(stderr,"%s: <directory>\n", argv[0]);
  21                 exit(1);
  22         }
  23
  24         directory = argv[1];
  25
  26         /* make it absolute */
  27         if (directory[0] != '/') {
  28                 char *cwd = getcwd(buf, sizeof(buf));
  29                 if (cwd == NULL) {
  30                         perror("cwd");
  31                         exit(1);
  32                 }
  33                 asprintf(&directory, "%s/%s", cwd, directory);
  34         }
  35
  36         /* resolve links etc */
  37         directory = realpath(directory, buf);
  38
  39         if (directory == NULL) {
  40                 perror("realpath");
  41                 exit(1);
  42         }
  43
  44         directory_len = strlen(directory);
  45
  46         d = opendir("/proc");
  47         if (d == NULL) {
  48                 perror("/proc");
  49                 exit(1);
  50         }
  51
  52         while ((de = readdir(d))) {
  53                 const char *name = de->d_name;
  54                 char *cwd_path, *real_cwd;
  55                 char cwd[PATH_MAX], buf2[PATH_MAX];
  56                 ssize_t link_size;
  57
  58                 if (!isdigit(name[0])) continue;
  59                 asprintf(&cwd_path, "/proc/%s/cwd", name);
  60                 link_size = readlink(cwd_path, cwd, sizeof(cwd));
  61                 free(cwd_path);
  62                 if (link_size == -1 || link_size >= sizeof(cwd)) {
  63                         continue;
  64                 }
  65
  66                 real_cwd = realpath(cwd, buf2);
  67                 if (real_cwd == NULL) {
  68                         continue;
  69                 }
  70
  71                 if (strncmp(directory, real_cwd, directory_len) == 0 &&
  72                     (real_cwd[directory_len] == 0 || real_cwd[directory_len] == '/')) {
  73                         /* kill it! */
  74                         printf("Killing process %s\n", name);
  75                         kill(atoi(name), SIGKILL);
  76                 }
  77
  78         }
  79
  80         return 0;
  81 }