utils

vidir.c (5146B)

---

 /*
  * vidir.c - rewrite of Joey Hess's vidir in C
  * usage: ./vidir [--verbose] [dir|file|-]
  */
 
 #include <ctype.h>
 #include <dirent.h>
 #include <errno.h>
 #include <libgen.h>
 #include <limits.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <sys/stat.h>
 #include <sys/wait.h>
 #include <unistd.h>
 
 #define MAX_FILES 10000
 
 typedef struct {
   int id;
   char *path;
 } Item;
 
 static int verbose = 0;
 static Item items[MAX_FILES];
 static int n_items = 0;
 static int error_flag = 0;
 
 void die(const char *msg) {
   perror(msg);
   exit(1);
 }
 
 void add_item(const char *path) {
   if (n_items >= MAX_FILES) {
     fprintf(stderr, "too many files\n");
     exit(1);
   }
   items[n_items].id = n_items + 1;
   items[n_items].path = strdup(path);
   n_items++;
 }
 
 void read_dir(const char *dirname) {
   DIR *dir = opendir(dirname);
   if (!dir) {
     fprintf(stderr, "cannot read %s: %s\n", dirname, strerror(errno));
     exit(1);
   }
   struct dirent *ent;
   while ((ent = readdir(dir))) {
     if (!strcmp(ent->d_name, ".") || !strcmp(ent->d_name, ".."))
       continue;
     char path[PATH_MAX];
     snprintf(path, sizeof(path), "%s/%s", dirname, ent->d_name);
     add_item(path);
   }
   closedir(dir);
 }
 
 int rm_path(const char *p) {
   struct stat st;
   if (lstat(p, &st) != 0)
     return -1;
   return S_ISDIR(st.st_mode) ? rmdir(p) : unlink(p);
 }
 
 void run_editor(const char *editor, const char *filename) {
   pid_t pid = fork();
   if (pid == 0) {
     execlp(editor, editor, filename, (char *)NULL);
     _exit(127);
   } else if (pid > 0) {
     waitpid(pid, NULL, 0);
   } else {
     die("fork");
   }
 }
 
 int main(int argc, char *argv[]) {
 #ifdef __OpenBSD__
   if (pledge("stdio rpath wpath cpath proc exec", NULL) == -1)
     die("pledge");
 #endif
 
   char tmpname[] = "/tmp/vidirXXXXXX";
   char line[PATH_MAX + 64];
   int fd = mkstemp(tmpname);
   if (fd < 0)
     die("mkstemp");
 
   /* Parse args */
   for (int i = 1; i < argc; i++) {
     if (!strcmp(argv[i], "--verbose") || !strcmp(argv[i], "-v")) {
       verbose = 1;
     } else if (!strcmp(argv[i], "-")) {
       while (fgets(line, sizeof(line), stdin)) {
         line[strcspn(line, "\r\n")] = 0;
         if (*line)
           add_item(line);
       }
     } else {
       struct stat st;
       if (stat(argv[i], &st) == 0 && S_ISDIR(st.st_mode))
         read_dir(argv[i]);
       else
         add_item(argv[i]);
     }
   }
   if (n_items == 0)
     read_dir(".");
 
   /* Write numbered list */
   FILE *tmp = fdopen(fd, "w");
   if (!tmp)
     die("fdopen");
   int digits = snprintf(NULL, 0, "%d", n_items);
   for (int i = 0; i < n_items; i++)
     fprintf(tmp, "%0*d\t%s\n", digits, items[i].id, items[i].path);
   fclose(tmp);
 
   /* Pick editor */
   char *editor = getenv("VISUAL");
   if (!editor)
     editor = getenv("EDITOR");
   if (!editor)
     editor = "vi";
 
   run_editor(editor, tmpname);
 
   int seen[MAX_FILES] = {0};
 
   /* Re-read edited list */
   tmp = fopen(tmpname, "r");
   if (!tmp)
     die("fopen tmp");
 
   char newname[PATH_MAX];
   while (fgets(line, sizeof(line), tmp)) {
     line[strcspn(line, "\r\n")] = 0;
     if (strlen(line) == 0)
       continue;
 
     int num;
     if (sscanf(line, "%d%[^\n]", &num, newname) < 1)
       continue;
 
     if (num <= 0 || num > n_items)
       continue;
 
     /* Mark this file as still existing in the list */
     seen[num - 1] = 1;
 
     char *p = newname;
     while (isspace((unsigned char)*p))
       p++;
 
     char *old = items[num - 1].path;
 
     /* Logic for renaming */
     if (strcmp(p, old) != 0) {
       char dirbuf[PATH_MAX];
       strncpy(dirbuf, p, sizeof(dirbuf) - 1);
       dirbuf[sizeof(dirbuf) - 1] = '\0';
       char *d = dirname(dirbuf);
       mkdir(d, 0777);
 
       /* Handle collisions */
       if (access(p, F_OK) == 0) {
         char collision_tmp[PATH_MAX + 16];
         int suffix = 0;
         snprintf(collision_tmp, sizeof(collision_tmp), "%s~", p);
         while (access(collision_tmp, F_OK) == 0) {
           suffix++;
           snprintf(collision_tmp, sizeof(collision_tmp), "%s~%d", p, suffix);
         }
         if (rename(p, collision_tmp) == 0) {
           if (verbose)
             printf("collision: renamed '%s' -> '%s'\n", p, collision_tmp);
           for (int j = 0; j < n_items; j++) {
             if (strcmp(items[j].path, p) == 0) {
               free(items[j].path);
               items[j].path = strdup(collision_tmp);
             }
           }
         }
       }
 
       if (rename(old, p) != 0) {
         fprintf(stderr, "%s -> %s: ", old, newname);
         perror("");
         error_flag = 1;
       } else {
         if (verbose)
           printf("renamed '%s' -> '%s'\n", old, p);
         free(items[num - 1].path);
         items[num - 1].path = strdup(p);
       }
     }
   }
   fclose(tmp);
 
   /* Delete files that were not in the edited file */
   for (int i = 0; i < n_items; i++) {
     if (!seen[i]) {
       if (rm_path(items[i].path) != 0) {
         fprintf(stderr, "%s: ", items[i].path);
         perror("cannot remove");
         error_flag = 1;
       } else if (verbose) {
         printf("removed '%s'\n", items[i].path);
       }
     }
     free(items[i].path);
   }
 
   unlink(tmpname);
   return error_flag;
 }