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                         if (buffer1.len && buffer1.buf[buffer1.len - 1] != '/')
 140                                 strbuf_addch(&buffer1, '/');
 141                         len1 = buffer1.len;
 142                 }
 143
 144                 if (name2) {
 145                         strbuf_addstr(&buffer2, name2);
 146                         if (buffer2.len && buffer2.buf[buffer2.len - 1] != '/')
 147                                 strbuf_addch(&buffer2, '/');
 148                         len2 = buffer2.len;
 149                 }
 150
 151                 for (i1 = i2 = 0; !ret && (i1 < p1.nr || i2 < p2.nr); ) {
 152                         const char *n1, *n2;
 153                         int comp;
 154
 155                         strbuf_setlen(&buffer1, len1);
 156                         strbuf_setlen(&buffer2, len2);
 157
 158                         if (i1 == p1.nr)
 159                                 comp = 1;
 160                         else if (i2 == p2.nr)
 161                                 comp = -1;
 162                         else
 163                                 comp = strcmp(p1.items[i1].string, p2.items[i2].string);
 164
 165                         if (comp > 0)
 166                                 n1 = NULL;
 167                         else {
 168                                 strbuf_addstr(&buffer1, p1.items[i1++].string);
 169                                 n1 = buffer1.buf;
 170                         }
 171
 172                         if (comp < 0)
 173                                 n2 = NULL;
 174                         else {
 175                                 strbuf_addstr(&buffer2, p2.items[i2++].string);
 176                                 n2 = buffer2.buf;
 177                         }
 178
 179                         ret = queue_diff(o, n1, n2);
 180                 }
 181                 string_list_clear(&p1, 0);
 182                 string_list_clear(&p2, 0);
 183                 strbuf_release(&buffer1);
 184                 strbuf_release(&buffer2);
 185
 186                 return ret;
 187         } else {
 188                 struct diff_filespec *d1, *d2;
 189
 190                 if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
 191                         unsigned tmp;
 192                         const char *tmp_c;
 193                         tmp = mode1; mode1 = mode2; mode2 = tmp;
 194                         tmp_c = name1; name1 = name2; name2 = tmp_c;
 195                 }
 196
 197                 d1 = noindex_filespec(name1, mode1);
 198                 d2 = noindex_filespec(name2, mode2);
 199                 diff_queue(&diff_queued_diff, d1, d2);
 200                 return 0;
 201         }
 202 }
 203
 204 /* append basename of F to D */
 205 static void append_basename(struct strbuf *path, const char *dir, const char *file)
 206 {
 207         const char *tail = strrchr(file, '/');
 208
 209         strbuf_addstr(path, dir);
 210         while (path->len && path->buf[path->len - 1] == '/')
 211                 path->len--;
 212         strbuf_addch(path, '/');
 213         strbuf_addstr(path, tail ? tail + 1 : file);
 214 }
 215
 216 /*
 217  * DWIM "diff D F" into "diff D/F F" and "diff F D" into "diff F D/F"
 218  * Note that we append the basename of F to D/, so "diff a/b/file D"
 219  * becomes "diff a/b/file D/file", not "diff a/b/file D/a/b/file".
 220  */
 221 static void fixup_paths(const char **path, struct strbuf *replacement)
 222 {
 223         unsigned int isdir0, isdir1;
 224
 225         if (path[0] == file_from_standard_input ||
 226             path[1] == file_from_standard_input)
 227                 return;
 228         isdir0 = is_directory(path[0]);
 229         isdir1 = is_directory(path[1]);
 230         if (isdir0 == isdir1)
 231                 return;
 232         if (isdir0) {
 233                 append_basename(replacement, path[0], path[1]);
 234                 path[0] = replacement->buf;
 235         } else {
 236                 append_basename(replacement, path[1], path[0]);
 237                 path[1] = replacement->buf;
 238         }
 239 }
 240
 241 void diff_no_index(struct rev_info *revs,
 242                    int argc, const char **argv,
 243                    const char *prefix)
 244 {
 245         int i, prefixlen;
 246         const char *paths[2];
 247         struct strbuf replacement = STRBUF_INIT;
 248
 249         diff_setup(&revs->diffopt);
 250         for (i = 1; i < argc - 2; ) {
 251                 int j;
 252                 if (!strcmp(argv[i], "--no-index"))
 253                         i++;
 254                 else if (!strcmp(argv[i], "--"))
 255                         i++;
 256                 else {
 257                         j = diff_opt_parse(&revs->diffopt, argv + i, argc - i);
 258                         if (j <= 0)
 259                                 die("invalid diff option/value: %s", argv[i]);
 260                         i += j;
 261                 }
 262         }
 263
 264         prefixlen = prefix ? strlen(prefix) : 0;
 265         for (i = 0; i < 2; i++) {
 266                 const char *p = argv[argc - 2 + i];
 267                 if (!strcmp(p, "-"))
 268                         /*
 269                          * stdin should be spelled as "-"; if you have
 270                          * path that is "-", spell it as "./-".
 271                          */
 272                         p = file_from_standard_input;
 273                 else if (prefixlen)
 274                         p = xstrdup(prefix_filename(prefix, prefixlen, p));
 275                 paths[i] = p;
 276         }
 277
 278         fixup_paths(paths, &replacement);
 279
 280         revs->diffopt.skip_stat_unmatch = 1;
 281         if (!revs->diffopt.output_format)
 282                 revs->diffopt.output_format = DIFF_FORMAT_PATCH;
 283
 284         DIFF_OPT_SET(&revs->diffopt, NO_INDEX);
 285
 286         revs->max_count = -2;
 287         diff_setup_done(&revs->diffopt);
 288
 289         setup_diff_pager(&revs->diffopt);
 290         DIFF_OPT_SET(&revs->diffopt, EXIT_WITH_STATUS);
 291
 292         if (queue_diff(&revs->diffopt, paths[0], paths[1]))
 293                 exit(1);
 294         diff_set_mnemonic_prefix(&revs->diffopt, "1/", "2/");
 295         diffcore_std(&revs->diffopt);
 296         diff_flush(&revs->diffopt);
 297
 298         strbuf_release(&replacement);
 299
 300         /*
 301          * The return code for --no-index imitates diff(1):
 302          * 0 = no changes, 1 = changes, else error
 303          */
 304         exit(diff_result_code(&revs->diffopt, 0));
 305 }