Andrew's git - gitweb.git/blob

   1#include "cache.h"
   2#include "builtin.h"
   3#include "exec_cmd.h"
   4#include "levenshtein.h"
   5#include "help.h"
   6#include "common-cmds.h"
   7
   8void add_cmdname(struct cmdnames *cmds, const char *name, int len)
   9{
  10        struct cmdname *ent = xmalloc(sizeof(*ent) + len + 1);
  11
  12        ent->len = len;
  13        memcpy(ent->name, name, len);
  14        ent->name[len] = 0;
  15
  16        ALLOC_GROW(cmds->names, cmds->cnt + 1, cmds->alloc);
  17        cmds->names[cmds->cnt++] = ent;
  18}
  19
  20static void clean_cmdnames(struct cmdnames *cmds)
  21{
  22        int i;
  23        for (i = 0; i < cmds->cnt; ++i)
  24                free(cmds->names[i]);
  25        free(cmds->names);
  26        cmds->cnt = 0;
  27        cmds->alloc = 0;
  28}
  29
  30static int cmdname_compare(const void *a_, const void *b_)
  31{
  32        struct cmdname *a = *(struct cmdname **)a_;
  33        struct cmdname *b = *(struct cmdname **)b_;
  34        return strcmp(a->name, b->name);
  35}
  36
  37static void uniq(struct cmdnames *cmds)
  38{
  39        int i, j;
  40
  41        if (!cmds->cnt)
  42                return;
  43
  44        for (i = j = 1; i < cmds->cnt; i++)
  45                if (strcmp(cmds->names[i]->name, cmds->names[i-1]->name))
  46                        cmds->names[j++] = cmds->names[i];
  47
  48        cmds->cnt = j;
  49}
  50
  51void exclude_cmds(struct cmdnames *cmds, struct cmdnames *excludes)
  52{
  53        int ci, cj, ei;
  54        int cmp;
  55
  56        ci = cj = ei = 0;
  57        while (ci < cmds->cnt && ei < excludes->cnt) {
  58                cmp = strcmp(cmds->names[ci]->name, excludes->names[ei]->name);
  59                if (cmp < 0)
  60                        cmds->names[cj++] = cmds->names[ci++];
  61                else if (cmp == 0)
  62                        ci++, ei++;
  63                else if (cmp > 0)
  64                        ei++;
  65        }
  66
  67        while (ci < cmds->cnt)
  68                cmds->names[cj++] = cmds->names[ci++];
  69
  70        cmds->cnt = cj;
  71}
  72
  73static void pretty_print_string_list(struct cmdnames *cmds, int longest)
  74{
  75        int cols = 1, rows;
  76        int space = longest + 1; /* min 1 SP between words */
  77        int max_cols = term_columns() - 1; /* don't print *on* the edge */
  78        int i, j;
  79
  80        if (space < max_cols)
  81                cols = max_cols / space;
  82        rows = DIV_ROUND_UP(cmds->cnt, cols);
  83
  84        for (i = 0; i < rows; i++) {
  85                printf("  ");
  86
  87                for (j = 0; j < cols; j++) {
  88                        int n = j * rows + i;
  89                        int size = space;
  90                        if (n >= cmds->cnt)
  91                                break;
  92                        if (j == cols-1 || n + rows >= cmds->cnt)
  93                                size = 1;
  94                        printf("%-*s", size, cmds->names[n]->name);
  95                }
  96                putchar('\n');
  97        }
  98}
  99
 100static int is_executable(const char *name)
 101{
 102        struct stat st;
 103
 104        if (stat(name, &st) || /* stat, not lstat */
 105            !S_ISREG(st.st_mode))
 106                return 0;
 107
 108#if defined(WIN32) || defined(__CYGWIN__)
 109#if defined(__CYGWIN__)
 110if ((st.st_mode & S_IXUSR) == 0)
 111#endif
 112{       /* cannot trust the executable bit, peek into the file instead */
 113        char buf[3] = { 0 };
 114        int n;
 115        int fd = open(name, O_RDONLY);
 116        st.st_mode &= ~S_IXUSR;
 117        if (fd >= 0) {
 118                n = read(fd, buf, 2);
 119                if (n == 2)
 120                        /* DOS executables start with "MZ" */
 121                        if (!strcmp(buf, "#!") || !strcmp(buf, "MZ"))
 122                                st.st_mode |= S_IXUSR;
 123                close(fd);
 124        }
 125}
 126#endif
 127        return st.st_mode & S_IXUSR;
 128}
 129
 130static void list_commands_in_dir(struct cmdnames *cmds,
 131                                         const char *path,
 132                                         const char *prefix)
 133{
 134        int prefix_len;
 135        DIR *dir = opendir(path);
 136        struct dirent *de;
 137        struct strbuf buf = STRBUF_INIT;
 138        int len;
 139
 140        if (!dir)
 141                return;
 142        if (!prefix)
 143                prefix = "git-";
 144        prefix_len = strlen(prefix);
 145
 146        strbuf_addf(&buf, "%s/", path);
 147        len = buf.len;
 148
 149        while ((de = readdir(dir)) != NULL) {
 150                int entlen;
 151
 152                if (prefixcmp(de->d_name, prefix))
 153                        continue;
 154
 155                strbuf_setlen(&buf, len);
 156                strbuf_addstr(&buf, de->d_name);
 157                if (!is_executable(buf.buf))
 158                        continue;
 159
 160                entlen = strlen(de->d_name) - prefix_len;
 161                if (has_extension(de->d_name, ".exe"))
 162                        entlen -= 4;
 163
 164                add_cmdname(cmds, de->d_name + prefix_len, entlen);
 165        }
 166        closedir(dir);
 167        strbuf_release(&buf);
 168}
 169
 170void load_command_list(const char *prefix,
 171                struct cmdnames *main_cmds,
 172                struct cmdnames *other_cmds)
 173{
 174        const char *env_path = getenv("PATH");
 175        const char *exec_path = git_exec_path();
 176
 177        if (exec_path) {
 178                list_commands_in_dir(main_cmds, exec_path, prefix);
 179                qsort(main_cmds->names, main_cmds->cnt,
 180                      sizeof(*main_cmds->names), cmdname_compare);
 181                uniq(main_cmds);
 182        }
 183
 184        if (env_path) {
 185                char *paths, *path, *colon;
 186                path = paths = xstrdup(env_path);
 187                while (1) {
 188                        if ((colon = strchr(path, PATH_SEP)))
 189                                *colon = 0;
 190                        if (!exec_path || strcmp(path, exec_path))
 191                                list_commands_in_dir(other_cmds, path, prefix);
 192
 193                        if (!colon)
 194                                break;
 195                        path = colon + 1;
 196                }
 197                free(paths);
 198
 199                qsort(other_cmds->names, other_cmds->cnt,
 200                      sizeof(*other_cmds->names), cmdname_compare);
 201                uniq(other_cmds);
 202        }
 203        exclude_cmds(other_cmds, main_cmds);
 204}
 205
 206void list_commands(const char *title, struct cmdnames *main_cmds,
 207                   struct cmdnames *other_cmds)
 208{
 209        int i, longest = 0;
 210
 211        for (i = 0; i < main_cmds->cnt; i++)
 212                if (longest < main_cmds->names[i]->len)
 213                        longest = main_cmds->names[i]->len;
 214        for (i = 0; i < other_cmds->cnt; i++)
 215                if (longest < other_cmds->names[i]->len)
 216                        longest = other_cmds->names[i]->len;
 217
 218        if (main_cmds->cnt) {
 219                const char *exec_path = git_exec_path();
 220                printf("available %s in '%s'\n", title, exec_path);
 221                printf("----------------");
 222                mput_char('-', strlen(title) + strlen(exec_path));
 223                putchar('\n');
 224                pretty_print_string_list(main_cmds, longest);
 225                putchar('\n');
 226        }
 227
 228        if (other_cmds->cnt) {
 229                printf("%s available from elsewhere on your $PATH\n", title);
 230                printf("---------------------------------------");
 231                mput_char('-', strlen(title));
 232                putchar('\n');
 233                pretty_print_string_list(other_cmds, longest);
 234                putchar('\n');
 235        }
 236}
 237
 238int is_in_cmdlist(struct cmdnames *c, const char *s)
 239{
 240        int i;
 241        for (i = 0; i < c->cnt; i++)
 242                if (!strcmp(s, c->names[i]->name))
 243                        return 1;
 244        return 0;
 245}
 246
 247static int autocorrect;
 248static struct cmdnames aliases;
 249
 250static int git_unknown_cmd_config(const char *var, const char *value, void *cb)
 251{
 252        if (!strcmp(var, "help.autocorrect"))
 253                autocorrect = git_config_int(var,value);
 254        /* Also use aliases for command lookup */
 255        if (!prefixcmp(var, "alias."))
 256                add_cmdname(&aliases, var + 6, strlen(var + 6));
 257
 258        return git_default_config(var, value, cb);
 259}
 260
 261static int levenshtein_compare(const void *p1, const void *p2)
 262{
 263        const struct cmdname *const *c1 = p1, *const *c2 = p2;
 264        const char *s1 = (*c1)->name, *s2 = (*c2)->name;
 265        int l1 = (*c1)->len;
 266        int l2 = (*c2)->len;
 267        return l1 != l2 ? l1 - l2 : strcmp(s1, s2);
 268}
 269
 270static void add_cmd_list(struct cmdnames *cmds, struct cmdnames *old)
 271{
 272        int i;
 273        ALLOC_GROW(cmds->names, cmds->cnt + old->cnt, cmds->alloc);
 274
 275        for (i = 0; i < old->cnt; i++)
 276                cmds->names[cmds->cnt++] = old->names[i];
 277        free(old->names);
 278        old->cnt = 0;
 279        old->names = NULL;
 280}
 281
 282/* An empirically derived magic number */
 283#define SIMILARITY_FLOOR 7
 284#define SIMILAR_ENOUGH(x) ((x) < SIMILARITY_FLOOR)
 285
 286static const char bad_interpreter_advice[] =
 287        N_("'%s' appears to be a git command, but we were not\n"
 288        "able to execute it. Maybe git-%s is broken?");
 289
 290const char *help_unknown_cmd(const char *cmd)
 291{
 292        int i, n, best_similarity = 0;
 293        struct cmdnames main_cmds, other_cmds;
 294
 295        memset(&main_cmds, 0, sizeof(main_cmds));
 296        memset(&other_cmds, 0, sizeof(other_cmds));
 297        memset(&aliases, 0, sizeof(aliases));
 298
 299        git_config(git_unknown_cmd_config, NULL);
 300
 301        load_command_list("git-", &main_cmds, &other_cmds);
 302
 303        add_cmd_list(&main_cmds, &aliases);
 304        add_cmd_list(&main_cmds, &other_cmds);
 305        qsort(main_cmds.names, main_cmds.cnt,
 306              sizeof(main_cmds.names), cmdname_compare);
 307        uniq(&main_cmds);
 308
 309        /* This abuses cmdname->len for levenshtein distance */
 310        for (i = 0, n = 0; i < main_cmds.cnt; i++) {
 311                int cmp = 0; /* avoid compiler stupidity */
 312                const char *candidate = main_cmds.names[i]->name;
 313
 314                /*
 315                 * An exact match means we have the command, but
 316                 * for some reason exec'ing it gave us ENOENT; probably
 317                 * it's a bad interpreter in the #! line.
 318                 */
 319                if (!strcmp(candidate, cmd))
 320                        die(_(bad_interpreter_advice), cmd, cmd);
 321
 322                /* Does the candidate appear in common_cmds list? */
 323                while (n < ARRAY_SIZE(common_cmds) &&
 324                       (cmp = strcmp(common_cmds[n].name, candidate)) < 0)
 325                        n++;
 326                if ((n < ARRAY_SIZE(common_cmds)) && !cmp) {
 327                        /* Yes, this is one of the common commands */
 328                        n++; /* use the entry from common_cmds[] */
 329                        if (!prefixcmp(candidate, cmd)) {
 330                                /* Give prefix match a very good score */
 331                                main_cmds.names[i]->len = 0;
 332                                continue;
 333                        }
 334                }
 335
 336                main_cmds.names[i]->len =
 337                        levenshtein(cmd, candidate, 0, 2, 1, 4) + 1;
 338        }
 339
 340        qsort(main_cmds.names, main_cmds.cnt,
 341              sizeof(*main_cmds.names), levenshtein_compare);
 342
 343        if (!main_cmds.cnt)
 344                die ("Uh oh. Your system reports no Git commands at all.");
 345
 346        /* skip and count prefix matches */
 347        for (n = 0; n < main_cmds.cnt && !main_cmds.names[n]->len; n++)
 348                ; /* still counting */
 349
 350        if (main_cmds.cnt <= n) {
 351                /* prefix matches with everything? that is too ambiguous */
 352                best_similarity = SIMILARITY_FLOOR + 1;
 353        } else {
 354                /* count all the most similar ones */
 355                for (best_similarity = main_cmds.names[n++]->len;
 356                     (n < main_cmds.cnt &&
 357                      best_similarity == main_cmds.names[n]->len);
 358                     n++)
 359                        ; /* still counting */
 360        }
 361        if (autocorrect && n == 1 && SIMILAR_ENOUGH(best_similarity)) {
 362                const char *assumed = main_cmds.names[0]->name;
 363                main_cmds.names[0] = NULL;
 364                clean_cmdnames(&main_cmds);
 365                fprintf(stderr, "WARNING: You called a Git command named '%s', "
 366                        "which does not exist.\n"
 367                        "Continuing under the assumption that you meant '%s'\n",
 368                        cmd, assumed);
 369                if (autocorrect > 0) {
 370                        fprintf(stderr, "in %0.1f seconds automatically...\n",
 371                                (float)autocorrect/10.0);
 372                        poll(NULL, 0, autocorrect * 100);
 373                }
 374                return assumed;
 375        }
 376
 377        fprintf(stderr, "git: '%s' is not a git command. See 'git --help'.\n", cmd);
 378
 379        if (SIMILAR_ENOUGH(best_similarity)) {
 380                fprintf(stderr, "\nDid you mean %s?\n",
 381                        n < 2 ? "this": "one of these");
 382
 383                for (i = 0; i < n; i++)
 384                        fprintf(stderr, "\t%s\n", main_cmds.names[i]->name);
 385        }
 386
 387        exit(1);
 388}
 389
 390int cmd_version(int argc, const char **argv, const char *prefix)
 391{
 392        printf("git version %s\n", git_version_string);
 393        return 0;
 394}