1b50da8f1a8107d81a005b025df971e8a497f940
   1/*
   2 * Check-out files from the "current cache directory"
   3 *
   4 * Copyright (C) 2005 Linus Torvalds
   5 *
   6 * Careful: order of argument flags does matter. For example,
   7 *
   8 *      checkout-cache -a -f file.c
   9 *
  10 * Will first check out all files listed in the cache (but not
  11 * overwrite any old ones), and then force-checkout "file.c" a
  12 * second time (ie that one _will_ overwrite any old contents
  13 * with the same filename).
  14 *
  15 * Also, just doing "checkout-cache" does nothing. You probably
  16 * meant "checkout-cache -a". And if you want to force it, you
  17 * want "checkout-cache -f -a".
  18 *
  19 * Intuitiveness is not the goal here. Repeatability is. The
  20 * reason for the "no arguments means no work" thing is that
  21 * from scripts you are supposed to be able to do things like
  22 *
  23 *      find . -name '*.h' -print0 | xargs -0 checkout-cache -f --
  24 *
  25 * which will force all existing *.h files to be replaced with
  26 * their cached copies. If an empty command line implied "all",
  27 * then this would force-refresh everything in the cache, which
  28 * was not the point.
  29 *
  30 * Oh, and the "--" is just a good idea when you know the rest
  31 * will be filenames. Just so that you wouldn't have a filename
  32 * of "-a" causing problems (not possible in the above example,
  33 * but get used to it in scripting!).
  34 */
  35#include "cache.h"
  36
  37static int force = 0, quiet = 0;
  38
  39static int write_entry(struct cache_entry *ce)
  40{
  41        int fd;
  42        void *new;
  43        unsigned long size;
  44        long wrote;
  45
  46        new = read_sha1_file(ce->sha1, "blob", &size);
  47        if (!new) {
  48                fprintf(stderr, "checkout-cache: unable to read sha1 file of %s (%s)\n",
  49                        ce->name, sha1_to_hex(ce->sha1));
  50                return -1;
  51        }
  52        fd = open(ce->name, O_WRONLY | O_CREAT | O_TRUNC, 0600);
  53        if (fd < 0) {
  54                fprintf(stderr, "checkout-cache: unable to create %s (%s)\n",
  55                        ce->name, strerror(errno));
  56                free(new);
  57                return -1;
  58        }
  59        wrote = write(fd, new, size);
  60        close(fd);
  61        free(new);
  62        if (wrote == size)
  63                return 0;
  64        fprintf(stderr, "checkout-cache: unable to write %s\n", ce->name);
  65        return -1;
  66}
  67
  68static int checkout_entry(struct cache_entry *ce)
  69{
  70        if (!force) {
  71                struct stat st;
  72
  73                if (!stat(ce->name, &st)) {
  74                        unsigned changed = cache_match_stat(ce, &st);
  75                        if (changed && !quiet)
  76                                fprintf(stderr, "checkout-cache: %s already exists\n", ce->name);
  77                        return 0;
  78                }
  79        }
  80        return write_entry(ce);
  81}
  82
  83static int checkout_file(const char *name)
  84{
  85        int pos = cache_name_pos(name, strlen(name));
  86        if (pos < 0) {
  87                if (!quiet)
  88                        fprintf(stderr, "checkout-cache: %s is not in the cache\n", name);
  89                return -1;
  90        }
  91        return checkout_entry(active_cache[pos]);
  92}
  93
  94static int checkout_all(void)
  95{
  96        int i;
  97
  98        for (i = 0; i < active_nr ; i++) {
  99                struct cache_entry *ce = active_cache[i];
 100                if (checkout_entry(ce) < 0)
 101                        return -1;
 102        }
 103        return 0;
 104}
 105
 106int main(int argc, char **argv)
 107{
 108        int i, force_filename = 0;
 109
 110        if (read_cache() < 0) {
 111                fprintf(stderr, "Invalid cache\n");
 112                exit(1);
 113        }
 114
 115        for (i = 1; i < argc; i++) {
 116                const char *arg = argv[i];
 117                if (!force_filename) {
 118                        if (!strcmp(arg, "-a")) {
 119                                checkout_all();
 120                                continue;
 121                        }
 122                        if (!strcmp(arg, "--")) {
 123                                force_filename = 1;
 124                                continue;
 125                        }
 126                        if (!strcmp(arg, "-f")) {
 127                                force = 1;
 128                                continue;
 129                        }
 130                        if (!strcmp(arg, "-q")) {
 131                                quiet = 1;
 132                                continue;
 133                        }
 134                }
 135                checkout_file(arg);
 136        }
 137        return 0;
 138}