help.con commit Merge branch 'tb/dedup-crlf-tests' into maint (86799c1)
   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#include "string-list.h"
   8#include "column.h"
   9#include "version.h"
  10#include "refs.h"
  11
  12void add_cmdname(struct cmdnames *cmds, const char *name, int len)
  13{
  14        struct cmdname *ent;
  15        FLEX_ALLOC_MEM(ent, name, name, len);
  16        ent->len = len;
  17
  18        ALLOC_GROW(cmds->names, cmds->cnt + 1, cmds->alloc);
  19        cmds->names[cmds->cnt++] = ent;
  20}
  21
  22static void clean_cmdnames(struct cmdnames *cmds)
  23{
  24        int i;
  25        for (i = 0; i < cmds->cnt; ++i)
  26                free(cmds->names[i]);
  27        free(cmds->names);
  28        cmds->cnt = 0;
  29        cmds->alloc = 0;
  30}
  31
  32static int cmdname_compare(const void *a_, const void *b_)
  33{
  34        struct cmdname *a = *(struct cmdname **)a_;
  35        struct cmdname *b = *(struct cmdname **)b_;
  36        return strcmp(a->name, b->name);
  37}
  38
  39static void uniq(struct cmdnames *cmds)
  40{
  41        int i, j;
  42
  43        if (!cmds->cnt)
  44                return;
  45
  46        for (i = j = 1; i < cmds->cnt; i++) {
  47                if (!strcmp(cmds->names[i]->name, cmds->names[j-1]->name))
  48                        free(cmds->names[i]);
  49                else
  50                        cmds->names[j++] = cmds->names[i];
  51        }
  52
  53        cmds->cnt = j;
  54}
  55
  56void exclude_cmds(struct cmdnames *cmds, struct cmdnames *excludes)
  57{
  58        int ci, cj, ei;
  59        int cmp;
  60
  61        ci = cj = ei = 0;
  62        while (ci < cmds->cnt && ei < excludes->cnt) {
  63                cmp = strcmp(cmds->names[ci]->name, excludes->names[ei]->name);
  64                if (cmp < 0)
  65                        cmds->names[cj++] = cmds->names[ci++];
  66                else if (cmp == 0) {
  67                        ei++;
  68                        free(cmds->names[ci++]);
  69                } else if (cmp > 0)
  70                        ei++;
  71        }
  72
  73        while (ci < cmds->cnt)
  74                cmds->names[cj++] = cmds->names[ci++];
  75
  76        cmds->cnt = cj;
  77}
  78
  79static void pretty_print_cmdnames(struct cmdnames *cmds, unsigned int colopts)
  80{
  81        struct string_list list = STRING_LIST_INIT_NODUP;
  82        struct column_options copts;
  83        int i;
  84
  85        for (i = 0; i < cmds->cnt; i++)
  86                string_list_append(&list, cmds->names[i]->name);
  87        /*
  88         * always enable column display, we only consult column.*
  89         * about layout strategy and stuff
  90         */
  91        colopts = (colopts & ~COL_ENABLE_MASK) | COL_ENABLED;
  92        memset(&copts, 0, sizeof(copts));
  93        copts.indent = "  ";
  94        copts.padding = 2;
  95        print_columns(&list, colopts, &copts);
  96        string_list_clear(&list, 0);
  97}
  98
  99static int is_executable(const char *name)
 100{
 101        struct stat st;
 102
 103        if (stat(name, &st) || /* stat, not lstat */
 104            !S_ISREG(st.st_mode))
 105                return 0;
 106
 107#if defined(GIT_WINDOWS_NATIVE)
 108        /*
 109         * On Windows there is no executable bit. The file extension
 110         * indicates whether it can be run as an executable, and Git
 111         * has special-handling to detect scripts and launch them
 112         * through the indicated script interpreter. We test for the
 113         * file extension first because virus scanners may make
 114         * it quite expensive to open many files.
 115         */
 116        if (ends_with(name, ".exe"))
 117                return S_IXUSR;
 118
 119{
 120        /*
 121         * Now that we know it does not have an executable extension,
 122         * peek into the file instead.
 123         */
 124        char buf[3] = { 0 };
 125        int n;
 126        int fd = open(name, O_RDONLY);
 127        st.st_mode &= ~S_IXUSR;
 128        if (fd >= 0) {
 129                n = read(fd, buf, 2);
 130                if (n == 2)
 131                        /* look for a she-bang */
 132                        if (!strcmp(buf, "#!"))
 133                                st.st_mode |= S_IXUSR;
 134                close(fd);
 135        }
 136}
 137#endif
 138        return st.st_mode & S_IXUSR;
 139}
 140
 141static void list_commands_in_dir(struct cmdnames *cmds,
 142                                         const char *path,
 143                                         const char *prefix)
 144{
 145        DIR *dir = opendir(path);
 146        struct dirent *de;
 147        struct strbuf buf = STRBUF_INIT;
 148        int len;
 149
 150        if (!dir)
 151                return;
 152        if (!prefix)
 153                prefix = "git-";
 154
 155        strbuf_addf(&buf, "%s/", path);
 156        len = buf.len;
 157
 158        while ((de = readdir(dir)) != NULL) {
 159                const char *ent;
 160                size_t entlen;
 161
 162                if (!skip_prefix(de->d_name, prefix, &ent))
 163                        continue;
 164
 165                strbuf_setlen(&buf, len);
 166                strbuf_addstr(&buf, de->d_name);
 167                if (!is_executable(buf.buf))
 168                        continue;
 169
 170                entlen = strlen(ent);
 171                strip_suffix(ent, ".exe", &entlen);
 172
 173                add_cmdname(cmds, ent, entlen);
 174        }
 175        closedir(dir);
 176        strbuf_release(&buf);
 177}
 178
 179void load_command_list(const char *prefix,
 180                struct cmdnames *main_cmds,
 181                struct cmdnames *other_cmds)
 182{
 183        const char *env_path = getenv("PATH");
 184        const char *exec_path = git_exec_path();
 185
 186        if (exec_path) {
 187                list_commands_in_dir(main_cmds, exec_path, prefix);
 188                QSORT(main_cmds->names, main_cmds->cnt, cmdname_compare);
 189                uniq(main_cmds);
 190        }
 191
 192        if (env_path) {
 193                char *paths, *path, *colon;
 194                path = paths = xstrdup(env_path);
 195                while (1) {
 196                        if ((colon = strchr(path, PATH_SEP)))
 197                                *colon = 0;
 198                        if (!exec_path || strcmp(path, exec_path))
 199                                list_commands_in_dir(other_cmds, path, prefix);
 200
 201                        if (!colon)
 202                                break;
 203                        path = colon + 1;
 204                }
 205                free(paths);
 206
 207                QSORT(other_cmds->names, other_cmds->cnt, cmdname_compare);
 208                uniq(other_cmds);
 209        }
 210        exclude_cmds(other_cmds, main_cmds);
 211}
 212
 213void list_commands(unsigned int colopts,
 214                   struct cmdnames *main_cmds, struct cmdnames *other_cmds)
 215{
 216        if (main_cmds->cnt) {
 217                const char *exec_path = git_exec_path();
 218                printf_ln(_("available git commands in '%s'"), exec_path);
 219                putchar('\n');
 220                pretty_print_cmdnames(main_cmds, colopts);
 221                putchar('\n');
 222        }
 223
 224        if (other_cmds->cnt) {
 225                printf_ln(_("git commands available from elsewhere on your $PATH"));
 226                putchar('\n');
 227                pretty_print_cmdnames(other_cmds, colopts);
 228                putchar('\n');
 229        }
 230}
 231
 232static int cmd_group_cmp(const void *elem1, const void *elem2)
 233{
 234        const struct cmdname_help *e1 = elem1;
 235        const struct cmdname_help *e2 = elem2;
 236
 237        if (e1->group < e2->group)
 238                return -1;
 239        if (e1->group > e2->group)
 240                return 1;
 241        return strcmp(e1->name, e2->name);
 242}
 243
 244void list_common_cmds_help(void)
 245{
 246        int i, longest = 0;
 247        int current_grp = -1;
 248
 249        for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
 250                if (longest < strlen(common_cmds[i].name))
 251                        longest = strlen(common_cmds[i].name);
 252        }
 253
 254        QSORT(common_cmds, ARRAY_SIZE(common_cmds), cmd_group_cmp);
 255
 256        puts(_("These are common Git commands used in various situations:"));
 257
 258        for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
 259                if (common_cmds[i].group != current_grp) {
 260                        printf("\n%s\n", _(common_cmd_groups[common_cmds[i].group]));
 261                        current_grp = common_cmds[i].group;
 262                }
 263
 264                printf("   %s   ", common_cmds[i].name);
 265                mput_char(' ', longest - strlen(common_cmds[i].name));
 266                puts(_(common_cmds[i].help));
 267        }
 268}
 269
 270int is_in_cmdlist(struct cmdnames *c, const char *s)
 271{
 272        int i;
 273        for (i = 0; i < c->cnt; i++)
 274                if (!strcmp(s, c->names[i]->name))
 275                        return 1;
 276        return 0;
 277}
 278
 279static int autocorrect;
 280static struct cmdnames aliases;
 281
 282static int git_unknown_cmd_config(const char *var, const char *value, void *cb)
 283{
 284        const char *p;
 285
 286        if (!strcmp(var, "help.autocorrect"))
 287                autocorrect = git_config_int(var,value);
 288        /* Also use aliases for command lookup */
 289        if (skip_prefix(var, "alias.", &p))
 290                add_cmdname(&aliases, p, strlen(p));
 291
 292        return git_default_config(var, value, cb);
 293}
 294
 295static int levenshtein_compare(const void *p1, const void *p2)
 296{
 297        const struct cmdname *const *c1 = p1, *const *c2 = p2;
 298        const char *s1 = (*c1)->name, *s2 = (*c2)->name;
 299        int l1 = (*c1)->len;
 300        int l2 = (*c2)->len;
 301        return l1 != l2 ? l1 - l2 : strcmp(s1, s2);
 302}
 303
 304static void add_cmd_list(struct cmdnames *cmds, struct cmdnames *old)
 305{
 306        int i;
 307        ALLOC_GROW(cmds->names, cmds->cnt + old->cnt, cmds->alloc);
 308
 309        for (i = 0; i < old->cnt; i++)
 310                cmds->names[cmds->cnt++] = old->names[i];
 311        free(old->names);
 312        old->cnt = 0;
 313        old->names = NULL;
 314}
 315
 316/* An empirically derived magic number */
 317#define SIMILARITY_FLOOR 7
 318#define SIMILAR_ENOUGH(x) ((x) < SIMILARITY_FLOOR)
 319
 320static const char bad_interpreter_advice[] =
 321        N_("'%s' appears to be a git command, but we were not\n"
 322        "able to execute it. Maybe git-%s is broken?");
 323
 324const char *help_unknown_cmd(const char *cmd)
 325{
 326        int i, n, best_similarity = 0;
 327        struct cmdnames main_cmds, other_cmds;
 328
 329        memset(&main_cmds, 0, sizeof(main_cmds));
 330        memset(&other_cmds, 0, sizeof(other_cmds));
 331        memset(&aliases, 0, sizeof(aliases));
 332
 333        git_config(git_unknown_cmd_config, NULL);
 334
 335        load_command_list("git-", &main_cmds, &other_cmds);
 336
 337        add_cmd_list(&main_cmds, &aliases);
 338        add_cmd_list(&main_cmds, &other_cmds);
 339        QSORT(main_cmds.names, main_cmds.cnt, cmdname_compare);
 340        uniq(&main_cmds);
 341
 342        /* This abuses cmdname->len for levenshtein distance */
 343        for (i = 0, n = 0; i < main_cmds.cnt; i++) {
 344                int cmp = 0; /* avoid compiler stupidity */
 345                const char *candidate = main_cmds.names[i]->name;
 346
 347                /*
 348                 * An exact match means we have the command, but
 349                 * for some reason exec'ing it gave us ENOENT; probably
 350                 * it's a bad interpreter in the #! line.
 351                 */
 352                if (!strcmp(candidate, cmd))
 353                        die(_(bad_interpreter_advice), cmd, cmd);
 354
 355                /* Does the candidate appear in common_cmds list? */
 356                while (n < ARRAY_SIZE(common_cmds) &&
 357                       (cmp = strcmp(common_cmds[n].name, candidate)) < 0)
 358                        n++;
 359                if ((n < ARRAY_SIZE(common_cmds)) && !cmp) {
 360                        /* Yes, this is one of the common commands */
 361                        n++; /* use the entry from common_cmds[] */
 362                        if (starts_with(candidate, cmd)) {
 363                                /* Give prefix match a very good score */
 364                                main_cmds.names[i]->len = 0;
 365                                continue;
 366                        }
 367                }
 368
 369                main_cmds.names[i]->len =
 370                        levenshtein(cmd, candidate, 0, 2, 1, 3) + 1;
 371        }
 372
 373        QSORT(main_cmds.names, main_cmds.cnt, levenshtein_compare);
 374
 375        if (!main_cmds.cnt)
 376                die(_("Uh oh. Your system reports no Git commands at all."));
 377
 378        /* skip and count prefix matches */
 379        for (n = 0; n < main_cmds.cnt && !main_cmds.names[n]->len; n++)
 380                ; /* still counting */
 381
 382        if (main_cmds.cnt <= n) {
 383                /* prefix matches with everything? that is too ambiguous */
 384                best_similarity = SIMILARITY_FLOOR + 1;
 385        } else {
 386                /* count all the most similar ones */
 387                for (best_similarity = main_cmds.names[n++]->len;
 388                     (n < main_cmds.cnt &&
 389                      best_similarity == main_cmds.names[n]->len);
 390                     n++)
 391                        ; /* still counting */
 392        }
 393        if (autocorrect && n == 1 && SIMILAR_ENOUGH(best_similarity)) {
 394                const char *assumed = main_cmds.names[0]->name;
 395                main_cmds.names[0] = NULL;
 396                clean_cmdnames(&main_cmds);
 397                fprintf_ln(stderr,
 398                           _("WARNING: You called a Git command named '%s', "
 399                             "which does not exist.\n"
 400                             "Continuing under the assumption that you meant '%s'"),
 401                        cmd, assumed);
 402                if (autocorrect > 0) {
 403                        fprintf_ln(stderr, _("in %0.1f seconds automatically..."),
 404                                (float)autocorrect/10.0);
 405                        sleep_millisec(autocorrect * 100);
 406                }
 407                return assumed;
 408        }
 409
 410        fprintf_ln(stderr, _("git: '%s' is not a git command. See 'git --help'."), cmd);
 411
 412        if (SIMILAR_ENOUGH(best_similarity)) {
 413                fprintf_ln(stderr,
 414                           Q_("\nThe most similar command is",
 415                              "\nThe most similar commands are",
 416                           n));
 417
 418                for (i = 0; i < n; i++)
 419                        fprintf(stderr, "\t%s\n", main_cmds.names[i]->name);
 420        }
 421
 422        exit(1);
 423}
 424
 425int cmd_version(int argc, const char **argv, const char *prefix)
 426{
 427        /*
 428         * The format of this string should be kept stable for compatibility
 429         * with external projects that rely on the output of "git version".
 430         */
 431        printf("git version %s\n", git_version_string);
 432        while (*++argv) {
 433                if (!strcmp(*argv, "--build-options")) {
 434                        printf("sizeof-long: %d\n", (int)sizeof(long));
 435                        /* NEEDSWORK: also save and output GIT-BUILD_OPTIONS? */
 436                }
 437        }
 438        return 0;
 439}
 440
 441struct similar_ref_cb {
 442        const char *base_ref;
 443        struct string_list *similar_refs;
 444};
 445
 446static int append_similar_ref(const char *refname, const struct object_id *oid,
 447                              int flags, void *cb_data)
 448{
 449        struct similar_ref_cb *cb = (struct similar_ref_cb *)(cb_data);
 450        char *branch = strrchr(refname, '/') + 1;
 451        const char *remote;
 452
 453        /* A remote branch of the same name is deemed similar */
 454        if (skip_prefix(refname, "refs/remotes/", &remote) &&
 455            !strcmp(branch, cb->base_ref))
 456                string_list_append(cb->similar_refs, remote);
 457        return 0;
 458}
 459
 460static struct string_list guess_refs(const char *ref)
 461{
 462        struct similar_ref_cb ref_cb;
 463        struct string_list similar_refs = STRING_LIST_INIT_NODUP;
 464
 465        ref_cb.base_ref = ref;
 466        ref_cb.similar_refs = &similar_refs;
 467        for_each_ref(append_similar_ref, &ref_cb);
 468        return similar_refs;
 469}
 470
 471void help_unknown_ref(const char *ref, const char *cmd, const char *error)
 472{
 473        int i;
 474        struct string_list suggested_refs = guess_refs(ref);
 475
 476        fprintf_ln(stderr, _("%s: %s - %s"), cmd, ref, error);
 477
 478        if (suggested_refs.nr > 0) {
 479                fprintf_ln(stderr,
 480                           Q_("\nDid you mean this?",
 481                              "\nDid you mean one of these?",
 482                              suggested_refs.nr));
 483                for (i = 0; i < suggested_refs.nr; i++)
 484                        fprintf(stderr, "\t%s\n", suggested_refs.items[i].string);
 485        }
 486
 487        string_list_clear(&suggested_refs, 0);
 488        exit(1);
 489}