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("error while reading from stdin %s",
  69                                      strerror(errno));
  70
  71         s->should_munmap = 0;
  72         s->data = strbuf_detach(&buf, &size);
  73         s->size = size;
  74         s->should_free = 1;
  75         s->is_stdin = 1;
  76         return 0;
  77 }
  78
  79 static struct diff_filespec *noindex_filespec(const char *name, int mode)
  80 {
  81         struct diff_filespec *s;
  82
  83         if (!name)
  84                 name = "/dev/null";
  85         s = alloc_filespec(name);
  86         fill_filespec(s, null_sha1, 0, mode);
  87         if (name == file_from_standard_input)
  88                 populate_from_stdin(s);
  89         return s;
  90 }
  91
  92 static int queue_diff(struct diff_options *o,
  93                       const char *name1, const char *name2)
  94 {
  95         int mode1 = 0, mode2 = 0;
  96
  97         if (get_mode(name1, &mode1) || get_mode(name2, &mode2))
  98                 return -1;
  99
 100         if (mode1 && mode2 && S_ISDIR(mode1) != S_ISDIR(mode2)) {
 101                 struct diff_filespec *d1, *d2;
 102
 103                 if (S_ISDIR(mode1)) {
 104                         /* 2 is file that is created */
 105                         d1 = noindex_filespec(NULL, 0);
 106                         d2 = noindex_filespec(name2, mode2);
 107                         name2 = NULL;
 108                         mode2 = 0;
 109                 } else {
 110                         /* 1 is file that is deleted */
 111                         d1 = noindex_filespec(name1, mode1);
 112                         d2 = noindex_filespec(NULL, 0);
 113                         name1 = NULL;
 114                         mode1 = 0;
 115                 }
 116                 /* emit that file */
 117                 diff_queue(&diff_queued_diff, d1, d2);
 118
 119                 /* and then let the entire directory be created or deleted */
 120         }
 121
 122         if (S_ISDIR(mode1) || S_ISDIR(mode2)) {
 123                 struct strbuf buffer1 = STRBUF_INIT;
 124                 struct strbuf buffer2 = STRBUF_INIT;
 125                 struct string_list p1 = STRING_LIST_INIT_DUP;
 126                 struct string_list p2 = STRING_LIST_INIT_DUP;
 127                 int i1, i2, ret = 0;
 128                 size_t len1 = 0, len2 = 0;
 129
 130                 if (name1 && read_directory_contents(name1, &p1))
 131                         return -1;
 132                 if (name2 && read_directory_contents(name2, &p2)) {
 133                         string_list_clear(&p1, 0);
 134                         return -1;
 135                 }
 136
 137                 if (name1) {
 138                         strbuf_addstr(&buffer1, name1);
 139                         strbuf_complete(&buffer1, '/');
 140                         len1 = buffer1.len;
 141                 }
 142
 143                 if (name2) {
 144                         strbuf_addstr(&buffer2, name2);
 145                         strbuf_complete(&buffer2, '/');
 146                         len2 = buffer2.len;
 147                 }
 148
 149                 for (i1 = i2 = 0; !ret && (i1 < p1.nr || i2 < p2.nr); ) {
 150                         const char *n1, *n2;
 151                         int comp;
 152
 153                         strbuf_setlen(&buffer1, len1);
 154                         strbuf_setlen(&buffer2, len2);
 155
 156                         if (i1 == p1.nr)
 157                                 comp = 1;
 158                         else if (i2 == p2.nr)
 159                                 comp = -1;
 160                         else
 161                                 comp = strcmp(p1.items[i1].string, p2.items[i2].string);
 162
 163                         if (comp > 0)
 164                                 n1 = NULL;
 165                         else {
 166                                 strbuf_addstr(&buffer1, p1.items[i1++].string);
 167                                 n1 = buffer1.buf;
 168                         }
 169
 170                         if (comp < 0)
 171                                 n2 = NULL;
 172                         else {
 173                                 strbuf_addstr(&buffer2, p2.items[i2++].string);
 174                                 n2 = buffer2.buf;
 175                         }
 176
 177                         ret = queue_diff(o, n1, n2);
 178                 }
 179                 string_list_clear(&p1, 0);
 180                 string_list_clear(&p2, 0);
 181                 strbuf_release(&buffer1);
 182                 strbuf_release(&buffer2);
 183
 184                 return ret;
 185         } else {
 186                 struct diff_filespec *d1, *d2;
 187
 188                 if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
 189                         unsigned tmp;
 190                         const char *tmp_c;
 191                         tmp = mode1; mode1 = mode2; mode2 = tmp;
 192                         tmp_c = name1; name1 = name2; name2 = tmp_c;
 193                 }
 194
 195                 d1 = noindex_filespec(name1, mode1);
 196                 d2 = noindex_filespec(name2, mode2);
 197                 diff_queue(&diff_queued_diff, d1, d2);
 198                 return 0;
 199         }
 200 }
 201
 202 /* append basename of F to D */
 203 static void append_basename(struct strbuf *path, const char *dir, const char *file)
 204 {
 205         const char *tail = strrchr(file, '/');
 206
 207         strbuf_addstr(path, dir);
 208         while (path->len && path->buf[path->len - 1] == '/')
 209                 path->len--;
 210         strbuf_addch(path, '/');
 211         strbuf_addstr(path, tail ? tail + 1 : file);
 212 }
 213
 214 /*
 215  * DWIM "diff D F" into "diff D/F F" and "diff F D" into "diff F D/F"
 216  * Note that we append the basename of F to D/, so "diff a/b/file D"
 217  * becomes "diff a/b/file D/file", not "diff a/b/file D/a/b/file".
 218  */
 219 static void fixup_paths(const char **path, struct strbuf *replacement)
 220 {
 221         unsigned int isdir0, isdir1;
 222
 223         if (path[0] == file_from_standard_input ||
 224             path[1] == file_from_standard_input)
 225                 return;
 226         isdir0 = is_directory(path[0]);
 227         isdir1 = is_directory(path[1]);
 228         if (isdir0 == isdir1)
 229                 return;
 230         if (isdir0) {
 231                 append_basename(replacement, path[0], path[1]);
 232                 path[0] = replacement->buf;
 233         } else {
 234                 append_basename(replacement, path[1], path[0]);
 235                 path[1] = replacement->buf;
 236         }
 237 }
 238
 239 void diff_no_index(struct rev_info *revs,
 240                    int argc, const char **argv)
 241 {
 242         int i, prefixlen;
 243         const char *paths[2];
 244         struct strbuf replacement = STRBUF_INIT;
 245         const char *prefix = revs->prefix;
 246
 247         diff_setup(&revs->diffopt);
 248         for (i = 1; i < argc - 2; ) {
 249                 int j;
 250                 if (!strcmp(argv[i], "--no-index"))
 251                         i++;
 252                 else if (!strcmp(argv[i], "--"))
 253                         i++;
 254                 else {
 255                         j = diff_opt_parse(&revs->diffopt, argv + i, argc - i,
 256                                            revs->prefix);
 257                         if (j <= 0)
 258                                 die("invalid diff option/value: %s", argv[i]);
 259                         i += j;
 260                 }
 261         }
 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
 277         fixup_paths(paths, &replacement);
 278
 279         revs->diffopt.skip_stat_unmatch = 1;
 280         if (!revs->diffopt.output_format)
 281                 revs->diffopt.output_format = DIFF_FORMAT_PATCH;
 282
 283         DIFF_OPT_SET(&revs->diffopt, NO_INDEX);
 284
 285         revs->max_count = -2;
 286         diff_setup_done(&revs->diffopt);
 287
 288         setup_diff_pager(&revs->diffopt);
 289         DIFF_OPT_SET(&revs->diffopt, EXIT_WITH_STATUS);
 290
 291         if (queue_diff(&revs->diffopt, paths[0], paths[1]))
 292                 exit(1);
 293         diff_set_mnemonic_prefix(&revs->diffopt, "1/", "2/");
 294         diffcore_std(&revs->diffopt);
 295         diff_flush(&revs->diffopt);
 296
 297         strbuf_release(&replacement);
 298
 299         /*
 300          * The return code for --no-index imitates diff(1):
 301          * 0 = no changes, 1 = changes, else error
 302          */
 303         exit(diff_result_code(&revs->diffopt, 0));
 304 }