diff-no-index.con commit blame: improve diagnosis for "--reverse NEW" (d993ce1)
   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
  20static 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 */
  41static const char file_from_standard_input[] = "-";
  42
  43static 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
  62static 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
  79static 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
  92static 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 */
 203static 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 */
 219static 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
 239void 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}