diff-no-index.c

   1 /*
   2  * "diff --no-index" support
   3  * Copyright (c) 2007 by Johannes Schindelin
   4  * Copyright (c) 2008 by Junio C Hamano
   5  */
   6
   7 #include "cache.h"
   8 #include "color.h"
   9 #include "commit.h"
  10 #include "blob.h"
  11 #include "tag.h"
  12 #include "diff.h"
  13 #include "diffcore.h"
  14 #include "revision.h"
  15 #include "log-tree.h"
  16 #include "builtin.h"
  17 #include "string-list.h"
  18
  19 static int read_directory(const char *path, struct string_list *list)
  20 {
  21         DIR *dir;
  22         struct dirent *e;
  23
  24         if (!(dir = opendir(path)))
  25                 return error("Could not open directory %s", path);
  26
  27         while ((e = readdir(dir)))
  28                 if (strcmp(".", e->d_name) && strcmp("..", e->d_name))
  29                         string_list_insert(list, e->d_name);
  30
  31         closedir(dir);
  32         return 0;
  33 }
  34
  35 /*
  36  * This should be "(standard input)" or something, but it will
  37  * probably expose many more breakages in the way no-index code
  38  * is bolted onto the diff callchain.
  39  */
  40 static const char file_from_standard_input[] = "-";
  41
  42 static int get_mode(const char *path, int *mode)
  43 {
  44         struct stat st;
  45
  46         if (!path || !strcmp(path, "/dev/null"))
  47                 *mode = 0;
  48 #ifdef _WIN32
  49         else if (!strcasecmp(path, "nul"))
  50                 *mode = 0;
  51 #endif
  52         else if (path == file_from_standard_input)
  53                 *mode = create_ce_mode(0666);
  54         else if (lstat(path, &st))
  55                 return error("Could not access '%s'", path);
  56         else
  57                 *mode = st.st_mode;
  58         return 0;
  59 }
  60
  61 static int populate_from_stdin(struct diff_filespec *s)
  62 {
  63         struct strbuf buf = STRBUF_INIT;
  64         size_t size = 0;
  65
  66         if (strbuf_read(&buf, 0, 0) < 0)
  67                 return error("error while reading from stdin %s",
  68                                      strerror(errno));
  69
  70         s->should_munmap = 0;
  71         s->data = strbuf_detach(&buf, &size);
  72         s->size = size;
  73         s->should_free = 1;
  74         s->is_stdin = 1;
  75         return 0;
  76 }
  77
  78 static struct diff_filespec *noindex_filespec(const char *name, int mode)
  79 {
  80         struct diff_filespec *s;
  81
  82         if (!name)
  83                 name = "/dev/null";
  84         s = alloc_filespec(name);
  85         fill_filespec(s, null_sha1, mode);
  86         if (name == file_from_standard_input)
  87                 populate_from_stdin(s);
  88         return s;
  89 }
  90
  91 static int queue_diff(struct diff_options *o,
  92                 const char *name1, const char *name2)
  93 {
  94         int mode1 = 0, mode2 = 0;
  95
  96         if (get_mode(name1, &mode1) || get_mode(name2, &mode2))
  97                 return -1;
  98
  99         if (mode1 && mode2 && S_ISDIR(mode1) != S_ISDIR(mode2))
 100                 return error("file/directory conflict: %s, %s", name1, name2);
 101
 102         if (S_ISDIR(mode1) || S_ISDIR(mode2)) {
 103                 char buffer1[PATH_MAX], buffer2[PATH_MAX];
 104                 struct string_list p1 = STRING_LIST_INIT_DUP;
 105                 struct string_list p2 = STRING_LIST_INIT_DUP;
 106                 int len1 = 0, len2 = 0, i1, i2, ret = 0;
 107
 108                 if (name1 && read_directory(name1, &p1))
 109                         return -1;
 110                 if (name2 && read_directory(name2, &p2)) {
 111                         string_list_clear(&p1, 0);
 112                         return -1;
 113                 }
 114
 115                 if (name1) {
 116                         len1 = strlen(name1);
 117                         if (len1 > 0 && name1[len1 - 1] == '/')
 118                                 len1--;
 119                         memcpy(buffer1, name1, len1);
 120                         buffer1[len1++] = '/';
 121                 }
 122
 123                 if (name2) {
 124                         len2 = strlen(name2);
 125                         if (len2 > 0 && name2[len2 - 1] == '/')
 126                                 len2--;
 127                         memcpy(buffer2, name2, len2);
 128                         buffer2[len2++] = '/';
 129                 }
 130
 131                 for (i1 = i2 = 0; !ret && (i1 < p1.nr || i2 < p2.nr); ) {
 132                         const char *n1, *n2;
 133                         int comp;
 134
 135                         if (i1 == p1.nr)
 136                                 comp = 1;
 137                         else if (i2 == p2.nr)
 138                                 comp = -1;
 139                         else
 140                                 comp = strcmp(p1.items[i1].string,
 141                                         p2.items[i2].string);
 142
 143                         if (comp > 0)
 144                                 n1 = NULL;
 145                         else {
 146                                 n1 = buffer1;
 147                                 strncpy(buffer1 + len1, p1.items[i1++].string,
 148                                                 PATH_MAX - len1);
 149                         }
 150
 151                         if (comp < 0)
 152                                 n2 = NULL;
 153                         else {
 154                                 n2 = buffer2;
 155                                 strncpy(buffer2 + len2, p2.items[i2++].string,
 156                                                 PATH_MAX - len2);
 157                         }
 158
 159                         ret = queue_diff(o, n1, n2);
 160                 }
 161                 string_list_clear(&p1, 0);
 162                 string_list_clear(&p2, 0);
 163
 164                 return ret;
 165         } else {
 166                 struct diff_filespec *d1, *d2;
 167
 168                 if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
 169                         unsigned tmp;
 170                         const char *tmp_c;
 171                         tmp = mode1; mode1 = mode2; mode2 = tmp;
 172                         tmp_c = name1; name1 = name2; name2 = tmp_c;
 173                 }
 174
 175                 d1 = noindex_filespec(name1, mode1);
 176                 d2 = noindex_filespec(name2, mode2);
 177                 diff_queue(&diff_queued_diff, d1, d2);
 178                 return 0;
 179         }
 180 }
 181
 182 static int path_outside_repo(const char *path)
 183 {
 184         const char *work_tree;
 185         size_t len;
 186
 187         if (!is_absolute_path(path))
 188                 return 0;
 189         work_tree = get_git_work_tree();
 190         if (!work_tree)
 191                 return 1;
 192         len = strlen(work_tree);
 193         if (strncmp(path, work_tree, len) ||
 194             (path[len] != '\0' && path[len] != '/'))
 195                 return 1;
 196         return 0;
 197 }
 198
 199 void diff_no_index(struct rev_info *revs,
 200                    int argc, const char **argv,
 201                    int nongit, const char *prefix)
 202 {
 203         int i, prefixlen;
 204         int no_index = 0;
 205         unsigned options = 0;
 206         const char *paths[2];
 207
 208         /* Were we asked to do --no-index explicitly? */
 209         for (i = 1; i < argc; i++) {
 210                 if (!strcmp(argv[i], "--")) {
 211                         i++;
 212                         break;
 213                 }
 214                 if (!strcmp(argv[i], "--no-index"))
 215                         no_index = 1;
 216                 if (argv[i][0] != '-')
 217                         break;
 218         }
 219
 220         if (!no_index && !nongit) {
 221                 /*
 222                  * Inside a git repository, without --no-index.  Only
 223                  * when a path outside the repository is given,
 224                  * e.g. "git diff /var/tmp/[12]", or "git diff
 225                  * Makefile /var/tmp/Makefile", allow it to be used as
 226                  * a colourful "diff" replacement.
 227                  */
 228                 if ((argc != i + 2) ||
 229                     (!path_outside_repo(argv[i]) &&
 230                      !path_outside_repo(argv[i+1])))
 231                         return;
 232         }
 233         if (argc != i + 2)
 234                 usagef("git diff %s <path> <path>",
 235                        no_index ? "--no-index" : "[--no-index]");
 236
 237         diff_setup(&revs->diffopt);
 238         for (i = 1; i < argc - 2; ) {
 239                 int j;
 240                 if (!strcmp(argv[i], "--no-index"))
 241                         i++;
 242                 else if (!strcmp(argv[i], "-q")) {
 243                         options |= DIFF_SILENT_ON_REMOVED;
 244                         i++;
 245                 }
 246                 else if (!strcmp(argv[i], "--"))
 247                         i++;
 248                 else {
 249                         j = diff_opt_parse(&revs->diffopt, argv + i, argc - i);
 250                         if (!j)
 251                                 die("invalid diff option/value: %s", argv[i]);
 252                         i += j;
 253                 }
 254         }
 255
 256         /*
 257          * If the user asked for our exit code then don't start a
 258          * pager or we would end up reporting its exit code instead.
 259          */
 260         if (!DIFF_OPT_TST(&revs->diffopt, EXIT_WITH_STATUS))
 261                 setup_pager();
 262
 263         prefixlen = prefix ? strlen(prefix) : 0;
 264         for (i = 0; i < 2; i++) {
 265                 const char *p = argv[argc - 2 + i];
 266                 if (!strcmp(p, "-"))
 267                         /*
 268                          * stdin should be spelled as "-"; if you have
 269                          * path that is "-", spell it as "./-".
 270                          */
 271                         p = file_from_standard_input;
 272                 else if (prefixlen)
 273                         p = xstrdup(prefix_filename(prefix, prefixlen, p));
 274                 paths[i] = p;
 275         }
 276         revs->diffopt.skip_stat_unmatch = 1;
 277         if (!revs->diffopt.output_format)
 278                 revs->diffopt.output_format = DIFF_FORMAT_PATCH;
 279
 280         DIFF_OPT_SET(&revs->diffopt, EXIT_WITH_STATUS);
 281         DIFF_OPT_SET(&revs->diffopt, NO_INDEX);
 282
 283         revs->max_count = -2;
 284         if (diff_setup_done(&revs->diffopt) < 0)
 285                 die("diff_setup_done failed");
 286
 287         if (queue_diff(&revs->diffopt, paths[0], paths[1]))
 288                 exit(1);
 289         diff_set_mnemonic_prefix(&revs->diffopt, "1/", "2/");
 290         diffcore_std(&revs->diffopt);
 291         diff_flush(&revs->diffopt);
 292
 293         /*
 294          * The return code for --no-index imitates diff(1):
 295          * 0 = no changes, 1 = changes, else error
 296          */
 297         exit(revs->diffopt.found_changes);
 298 }