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 #include "dir.h"
  19
  20 static int read_directory_contents(const char *path, struct string_list *list)
  21 {
  22         DIR *dir;
  23         struct dirent *e;
  24
  25         if (!(dir = opendir(path)))
  26                 return error("Could not open directory %s", path);
  27
  28         while ((e = readdir(dir)))
  29                 if (!is_dot_or_dotdot(e->d_name))
  30                         string_list_insert(list, e->d_name);
  31
  32         closedir(dir);
  33         return 0;
  34 }
  35
  36 /*
  37  * This should be "(standard input)" or something, but it will
  38  * probably expose many more breakages in the way no-index code
  39  * is bolted onto the diff callchain.
  40  */
  41 static const char file_from_standard_input[] = "-";
  42
  43 static int get_mode(const char *path, int *mode)
  44 {
  45         struct stat st;
  46
  47         if (!path || !strcmp(path, "/dev/null"))
  48                 *mode = 0;
  49 #ifdef GIT_WINDOWS_NATIVE
  50         else if (!strcasecmp(path, "nul"))
  51                 *mode = 0;
  52 #endif
  53         else if (path == file_from_standard_input)
  54                 *mode = create_ce_mode(0666);
  55         else if (lstat(path, &st))
  56                 return error("Could not access '%s'", path);
  57         else
  58                 *mode = st.st_mode;
  59         return 0;
  60 }
  61
  62 static int populate_from_stdin(struct diff_filespec *s)
  63 {
  64         struct strbuf buf = STRBUF_INIT;
  65         size_t size = 0;
  66
  67         if (strbuf_read(&buf, 0, 0) < 0)
  68                 return error_errno("error while reading from stdin");
  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, 0, 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                 struct diff_filespec *d1, *d2;
 101
 102                 if (S_ISDIR(mode1)) {
 103                         /* 2 is file that is created */
 104                         d1 = noindex_filespec(NULL, 0);
 105                         d2 = noindex_filespec(name2, mode2);
 106                         name2 = NULL;
 107                         mode2 = 0;
 108                 } else {
 109                         /* 1 is file that is deleted */
 110                         d1 = noindex_filespec(name1, mode1);
 111                         d2 = noindex_filespec(NULL, 0);
 112                         name1 = NULL;
 113                         mode1 = 0;
 114                 }
 115                 /* emit that file */
 116                 diff_queue(&diff_queued_diff, d1, d2);
 117
 118                 /* and then let the entire directory be created or deleted */
 119         }
 120
 121         if (S_ISDIR(mode1) || S_ISDIR(mode2)) {
 122                 struct strbuf buffer1 = STRBUF_INIT;
 123                 struct strbuf buffer2 = STRBUF_INIT;
 124                 struct string_list p1 = STRING_LIST_INIT_DUP;
 125                 struct string_list p2 = STRING_LIST_INIT_DUP;
 126                 int i1, i2, ret = 0;
 127                 size_t len1 = 0, len2 = 0;
 128
 129                 if (name1 && read_directory_contents(name1, &p1))
 130                         return -1;
 131                 if (name2 && read_directory_contents(name2, &p2)) {
 132                         string_list_clear(&p1, 0);
 133                         return -1;
 134                 }
 135
 136                 if (name1) {
 137                         strbuf_addstr(&buffer1, name1);
 138                         strbuf_complete(&buffer1, '/');
 139                         len1 = buffer1.len;
 140                 }
 141
 142                 if (name2) {
 143                         strbuf_addstr(&buffer2, name2);
 144                         strbuf_complete(&buffer2, '/');
 145                         len2 = buffer2.len;
 146                 }
 147
 148                 for (i1 = i2 = 0; !ret && (i1 < p1.nr || i2 < p2.nr); ) {
 149                         const char *n1, *n2;
 150                         int comp;
 151
 152                         strbuf_setlen(&buffer1, len1);
 153                         strbuf_setlen(&buffer2, len2);
 154
 155                         if (i1 == p1.nr)
 156                                 comp = 1;
 157                         else if (i2 == p2.nr)
 158                                 comp = -1;
 159                         else
 160                                 comp = strcmp(p1.items[i1].string, p2.items[i2].string);
 161
 162                         if (comp > 0)
 163                                 n1 = NULL;
 164                         else {
 165                                 strbuf_addstr(&buffer1, p1.items[i1++].string);
 166                                 n1 = buffer1.buf;
 167                         }
 168
 169                         if (comp < 0)
 170                                 n2 = NULL;
 171                         else {
 172                                 strbuf_addstr(&buffer2, p2.items[i2++].string);
 173                                 n2 = buffer2.buf;
 174                         }
 175
 176                         ret = queue_diff(o, n1, n2);
 177                 }
 178                 string_list_clear(&p1, 0);
 179                 string_list_clear(&p2, 0);
 180                 strbuf_release(&buffer1);
 181                 strbuf_release(&buffer2);
 182
 183                 return ret;
 184         } else {
 185                 struct diff_filespec *d1, *d2;
 186
 187                 if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
 188                         unsigned tmp;
 189                         const char *tmp_c;
 190                         tmp = mode1; mode1 = mode2; mode2 = tmp;
 191                         tmp_c = name1; name1 = name2; name2 = tmp_c;
 192                 }
 193
 194                 d1 = noindex_filespec(name1, mode1);
 195                 d2 = noindex_filespec(name2, mode2);
 196                 diff_queue(&diff_queued_diff, d1, d2);
 197                 return 0;
 198         }
 199 }
 200
 201 /* append basename of F to D */
 202 static void append_basename(struct strbuf *path, const char *dir, const char *file)
 203 {
 204         const char *tail = strrchr(file, '/');
 205
 206         strbuf_addstr(path, dir);
 207         while (path->len && path->buf[path->len - 1] == '/')
 208                 path->len--;
 209         strbuf_addch(path, '/');
 210         strbuf_addstr(path, tail ? tail + 1 : file);
 211 }
 212
 213 /*
 214  * DWIM "diff D F" into "diff D/F F" and "diff F D" into "diff F D/F"
 215  * Note that we append the basename of F to D/, so "diff a/b/file D"
 216  * becomes "diff a/b/file D/file", not "diff a/b/file D/a/b/file".
 217  */
 218 static void fixup_paths(const char **path, struct strbuf *replacement)
 219 {
 220         unsigned int isdir0, isdir1;
 221
 222         if (path[0] == file_from_standard_input ||
 223             path[1] == file_from_standard_input)
 224                 return;
 225         isdir0 = is_directory(path[0]);
 226         isdir1 = is_directory(path[1]);
 227         if (isdir0 == isdir1)
 228                 return;
 229         if (isdir0) {
 230                 append_basename(replacement, path[0], path[1]);
 231                 path[0] = replacement->buf;
 232         } else {
 233                 append_basename(replacement, path[1], path[0]);
 234                 path[1] = replacement->buf;
 235         }
 236 }
 237
 238 void diff_no_index(struct rev_info *revs,
 239                    int argc, const char **argv)
 240 {
 241         int i, prefixlen;
 242         const char *paths[2];
 243         struct strbuf replacement = STRBUF_INIT;
 244         const char *prefix = revs->prefix;
 245
 246         diff_setup(&revs->diffopt);
 247         for (i = 1; i < argc - 2; ) {
 248                 int j;
 249                 if (!strcmp(argv[i], "--no-index"))
 250                         i++;
 251                 else if (!strcmp(argv[i], "--"))
 252                         i++;
 253                 else {
 254                         j = diff_opt_parse(&revs->diffopt, argv + i, argc - i,
 255                                            revs->prefix);
 256                         if (j <= 0)
 257                                 die("invalid diff option/value: %s", argv[i]);
 258                         i += j;
 259                 }
 260         }
 261
 262         prefixlen = prefix ? strlen(prefix) : 0;
 263         for (i = 0; i < 2; i++) {
 264                 const char *p = argv[argc - 2 + i];
 265                 if (!strcmp(p, "-"))
 266                         /*
 267                          * stdin should be spelled as "-"; if you have
 268                          * path that is "-", spell it as "./-".
 269                          */
 270                         p = file_from_standard_input;
 271                 else if (prefixlen)
 272                         p = xstrdup(prefix_filename(prefix, prefixlen, p));
 273                 paths[i] = p;
 274         }
 275
 276         fixup_paths(paths, &replacement);
 277
 278         revs->diffopt.skip_stat_unmatch = 1;
 279         if (!revs->diffopt.output_format)
 280                 revs->diffopt.output_format = DIFF_FORMAT_PATCH;
 281
 282         DIFF_OPT_SET(&revs->diffopt, NO_INDEX);
 283
 284         revs->max_count = -2;
 285         diff_setup_done(&revs->diffopt);
 286
 287         setup_diff_pager(&revs->diffopt);
 288         DIFF_OPT_SET(&revs->diffopt, EXIT_WITH_STATUS);
 289
 290         if (queue_diff(&revs->diffopt, paths[0], paths[1]))
 291                 exit(1);
 292         diff_set_mnemonic_prefix(&revs->diffopt, "1/", "2/");
 293         diffcore_std(&revs->diffopt);
 294         diff_flush(&revs->diffopt);
 295
 296         strbuf_release(&replacement);
 297
 298         /*
 299          * The return code for --no-index imitates diff(1):
 300          * 0 = no changes, 1 = changes, else error
 301          */
 302         exit(diff_result_code(&revs->diffopt, 0));
 303 }