chmod_u.c

/*	chmod - toolbox
	Copyright 2015-2018 Rivoreo

	This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

	This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
*/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <dirent.h>
#include <errno.h>
#include <limits.h>
#include <sys/stat.h>
#include "str2mode.h"
#include <unistd.h>
#include <time.h>

static int recurse_chmod(const char *path, int mode) {
	struct dirent *dp;
	DIR *dir = opendir(path);
	if(dir == NULL) {
		// not a directory, carry on
		return 0;
	}
	char *subpath = malloc(sizeof(char) * PATH_MAX);
	int pathlen = strlen(path);
	int r = 0;
	while((dp = readdir(dir)) != NULL) {
		if(strcmp(dp->d_name, ".") == 0 || strcmp(dp->d_name, "..") == 0) continue;

		if(strlen(dp->d_name) + pathlen + 2/*NUL and slash*/ > PATH_MAX) {
			fprintf(stderr, "Invalid path specified: too long\n");
			return -1;
		}

		strcpy(subpath, path);
		strcat(subpath, "/");
		strcat(subpath, dp->d_name);

		if(chmod(subpath, mode) < 0) {
			fprintf(stderr, "Unable to chmod %s: %s\n", subpath, strerror(errno));
			return -1;
		}

		if(recurse_chmod(subpath, mode) < 0) r = -1;
	}
	free(subpath);
	closedir(dir);
	return r;
}

static void usage() {
	fprintf(stderr, "Usage: chmod"
#if defined _WIN32 && !defined _WINDOWSNT_NATIVE
			".exe"
#endif
			" [<option>] <mode> <file>\n");
	fprintf(stderr, "  -R, --recursive         change files and directories recursively\n");
	fprintf(stderr, "  --help                  display this help and exit\n");
}

int chmod_main(int argc, char **argv) {
	int i;

	if(argc < 3 || strcmp(argv[1], "--help") == 0) {
		usage();
		return -1;
	}

	int recursive = (strcmp(argv[1], "-R") == 0 ||
			strcmp(argv[1], "--recursive") == 0) ? 1 : 0;

	if(recursive && argc < 4) {
		usage();
		return 10;
	}

	if(recursive) {
		argc--;
		argv++;
	}

	mode_t mode = STR2MODE(argv[1]);
	if(mode == (mode_t)-1) {
		fprintf(stderr, "chmod: Bad mode '%s'\n", argv[1]);
		return 10;
	}

	int r = 0;
	for(i = 2; i < argc; i++) {
		if(chmod(argv[i], mode) < 0) {
			fprintf(stderr, "Unable to chmod %s: %s\n", argv[i], strerror(errno));
			r = 1;
		}
		if(recursive && recurse_chmod(argv[i], mode) < 0) {
			r = 1;
		}
	}
	return r;
}