help.con commit Merge branch 'hv/doc-commit-reference-style' (d012326)
   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{       /* cannot trust the executable bit, peek into the file instead */
 109        char buf[3] = { 0 };
 110        int n;
 111        int fd = open(name, O_RDONLY);
 112        st.st_mode &= ~S_IXUSR;
 113        if (fd >= 0) {
 114                n = read(fd, buf, 2);
 115                if (n == 2)
 116                        /* DOS executables start with "MZ" */
 117                        if (!strcmp(buf, "#!") || !strcmp(buf, "MZ"))
 118                                st.st_mode |= S_IXUSR;
 119                close(fd);
 120        }
 121}
 122#endif
 123        return st.st_mode & S_IXUSR;
 124}
 125
 126static void list_commands_in_dir(struct cmdnames *cmds,
 127                                         const char *path,
 128                                         const char *prefix)
 129{
 130        DIR *dir = opendir(path);
 131        struct dirent *de;
 132        struct strbuf buf = STRBUF_INIT;
 133        int len;
 134
 135        if (!dir)
 136                return;
 137        if (!prefix)
 138                prefix = "git-";
 139
 140        strbuf_addf(&buf, "%s/", path);
 141        len = buf.len;
 142
 143        while ((de = readdir(dir)) != NULL) {
 144                const char *ent;
 145                size_t entlen;
 146
 147                if (!skip_prefix(de->d_name, prefix, &ent))
 148                        continue;
 149
 150                strbuf_setlen(&buf, len);
 151                strbuf_addstr(&buf, de->d_name);
 152                if (!is_executable(buf.buf))
 153                        continue;
 154
 155                entlen = strlen(ent);
 156                strip_suffix(ent, ".exe", &entlen);
 157
 158                add_cmdname(cmds, ent, entlen);
 159        }
 160        closedir(dir);
 161        strbuf_release(&buf);
 162}
 163
 164void load_command_list(const char *prefix,
 165                struct cmdnames *main_cmds,
 166                struct cmdnames *other_cmds)
 167{
 168        const char *env_path = getenv("PATH");
 169        const char *exec_path = git_exec_path();
 170
 171        if (exec_path) {
 172                list_commands_in_dir(main_cmds, exec_path, prefix);
 173                qsort(main_cmds->names, main_cmds->cnt,
 174                      sizeof(*main_cmds->names), cmdname_compare);
 175                uniq(main_cmds);
 176        }
 177
 178        if (env_path) {
 179                char *paths, *path, *colon;
 180                path = paths = xstrdup(env_path);
 181                while (1) {
 182                        if ((colon = strchr(path, PATH_SEP)))
 183                                *colon = 0;
 184                        if (!exec_path || strcmp(path, exec_path))
 185                                list_commands_in_dir(other_cmds, path, prefix);
 186
 187                        if (!colon)
 188                                break;
 189                        path = colon + 1;
 190                }
 191                free(paths);
 192
 193                qsort(other_cmds->names, other_cmds->cnt,
 194                      sizeof(*other_cmds->names), cmdname_compare);
 195                uniq(other_cmds);
 196        }
 197        exclude_cmds(other_cmds, main_cmds);
 198}
 199
 200void list_commands(unsigned int colopts,
 201                   struct cmdnames *main_cmds, struct cmdnames *other_cmds)
 202{
 203        if (main_cmds->cnt) {
 204                const char *exec_path = git_exec_path();
 205                printf_ln(_("available git commands in '%s'"), exec_path);
 206                putchar('\n');
 207                pretty_print_cmdnames(main_cmds, colopts);
 208                putchar('\n');
 209        }
 210
 211        if (other_cmds->cnt) {
 212                printf_ln(_("git commands available from elsewhere on your $PATH"));
 213                putchar('\n');
 214                pretty_print_cmdnames(other_cmds, colopts);
 215                putchar('\n');
 216        }
 217}
 218
 219static int cmd_group_cmp(const void *elem1, const void *elem2)
 220{
 221        const struct cmdname_help *e1 = elem1;
 222        const struct cmdname_help *e2 = elem2;
 223
 224        if (e1->group < e2->group)
 225                return -1;
 226        if (e1->group > e2->group)
 227                return 1;
 228        return strcmp(e1->name, e2->name);
 229}
 230
 231void list_common_cmds_help(void)
 232{
 233        int i, longest = 0;
 234        int current_grp = -1;
 235
 236        for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
 237                if (longest < strlen(common_cmds[i].name))
 238                        longest = strlen(common_cmds[i].name);
 239        }
 240
 241        qsort(common_cmds, ARRAY_SIZE(common_cmds),
 242                sizeof(common_cmds[0]), cmd_group_cmp);
 243
 244        puts(_("These are common Git commands used in various situations:"));
 245
 246        for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
 247                if (common_cmds[i].group != current_grp) {
 248                        printf("\n%s\n", _(common_cmd_groups[common_cmds[i].group]));
 249                        current_grp = common_cmds[i].group;
 250                }
 251
 252                printf("   %s   ", common_cmds[i].name);
 253                mput_char(' ', longest - strlen(common_cmds[i].name));
 254                puts(_(common_cmds[i].help));
 255        }
 256}
 257
 258int is_in_cmdlist(struct cmdnames *c, const char *s)
 259{
 260        int i;
 261        for (i = 0; i < c->cnt; i++)
 262                if (!strcmp(s, c->names[i]->name))
 263                        return 1;
 264        return 0;
 265}
 266
 267static int autocorrect;
 268static struct cmdnames aliases;
 269
 270static int git_unknown_cmd_config(const char *var, const char *value, void *cb)
 271{
 272        const char *p;
 273
 274        if (!strcmp(var, "help.autocorrect"))
 275                autocorrect = git_config_int(var,value);
 276        /* Also use aliases for command lookup */
 277        if (skip_prefix(var, "alias.", &p))
 278                add_cmdname(&aliases, p, strlen(p));
 279
 280        return git_default_config(var, value, cb);
 281}
 282
 283static int levenshtein_compare(const void *p1, const void *p2)
 284{
 285        const struct cmdname *const *c1 = p1, *const *c2 = p2;
 286        const char *s1 = (*c1)->name, *s2 = (*c2)->name;
 287        int l1 = (*c1)->len;
 288        int l2 = (*c2)->len;
 289        return l1 != l2 ? l1 - l2 : strcmp(s1, s2);
 290}
 291
 292static void add_cmd_list(struct cmdnames *cmds, struct cmdnames *old)
 293{
 294        int i;
 295        ALLOC_GROW(cmds->names, cmds->cnt + old->cnt, cmds->alloc);
 296
 297        for (i = 0; i < old->cnt; i++)
 298                cmds->names[cmds->cnt++] = old->names[i];
 299        free(old->names);
 300        old->cnt = 0;
 301        old->names = NULL;
 302}
 303
 304/* An empirically derived magic number */
 305#define SIMILARITY_FLOOR 7
 306#define SIMILAR_ENOUGH(x) ((x) < SIMILARITY_FLOOR)
 307
 308static const char bad_interpreter_advice[] =
 309        N_("'%s' appears to be a git command, but we were not\n"
 310        "able to execute it. Maybe git-%s is broken?");
 311
 312const char *help_unknown_cmd(const char *cmd)
 313{
 314        int i, n, best_similarity = 0;
 315        struct cmdnames main_cmds, other_cmds;
 316
 317        memset(&main_cmds, 0, sizeof(main_cmds));
 318        memset(&other_cmds, 0, sizeof(other_cmds));
 319        memset(&aliases, 0, sizeof(aliases));
 320
 321        git_config(git_unknown_cmd_config, NULL);
 322
 323        load_command_list("git-", &main_cmds, &other_cmds);
 324
 325        add_cmd_list(&main_cmds, &aliases);
 326        add_cmd_list(&main_cmds, &other_cmds);
 327        qsort(main_cmds.names, main_cmds.cnt,
 328              sizeof(*main_cmds.names), cmdname_compare);
 329        uniq(&main_cmds);
 330
 331        /* This abuses cmdname->len for levenshtein distance */
 332        for (i = 0, n = 0; i < main_cmds.cnt; i++) {
 333                int cmp = 0; /* avoid compiler stupidity */
 334                const char *candidate = main_cmds.names[i]->name;
 335
 336                /*
 337                 * An exact match means we have the command, but
 338                 * for some reason exec'ing it gave us ENOENT; probably
 339                 * it's a bad interpreter in the #! line.
 340                 */
 341                if (!strcmp(candidate, cmd))
 342                        die(_(bad_interpreter_advice), cmd, cmd);
 343
 344                /* Does the candidate appear in common_cmds list? */
 345                while (n < ARRAY_SIZE(common_cmds) &&
 346                       (cmp = strcmp(common_cmds[n].name, candidate)) < 0)
 347                        n++;
 348                if ((n < ARRAY_SIZE(common_cmds)) && !cmp) {
 349                        /* Yes, this is one of the common commands */
 350                        n++; /* use the entry from common_cmds[] */
 351                        if (starts_with(candidate, cmd)) {
 352                                /* Give prefix match a very good score */
 353                                main_cmds.names[i]->len = 0;
 354                                continue;
 355                        }
 356                }
 357
 358                main_cmds.names[i]->len =
 359                        levenshtein(cmd, candidate, 0, 2, 1, 3) + 1;
 360        }
 361
 362        qsort(main_cmds.names, main_cmds.cnt,
 363              sizeof(*main_cmds.names), levenshtein_compare);
 364
 365        if (!main_cmds.cnt)
 366                die(_("Uh oh. Your system reports no Git commands at all."));
 367
 368        /* skip and count prefix matches */
 369        for (n = 0; n < main_cmds.cnt && !main_cmds.names[n]->len; n++)
 370                ; /* still counting */
 371
 372        if (main_cmds.cnt <= n) {
 373                /* prefix matches with everything? that is too ambiguous */
 374                best_similarity = SIMILARITY_FLOOR + 1;
 375        } else {
 376                /* count all the most similar ones */
 377                for (best_similarity = main_cmds.names[n++]->len;
 378                     (n < main_cmds.cnt &&
 379                      best_similarity == main_cmds.names[n]->len);
 380                     n++)
 381                        ; /* still counting */
 382        }
 383        if (autocorrect && n == 1 && SIMILAR_ENOUGH(best_similarity)) {
 384                const char *assumed = main_cmds.names[0]->name;
 385                main_cmds.names[0] = NULL;
 386                clean_cmdnames(&main_cmds);
 387                fprintf_ln(stderr,
 388                           _("WARNING: You called a Git command named '%s', "
 389                             "which does not exist.\n"
 390                             "Continuing under the assumption that you meant '%s'"),
 391                        cmd, assumed);
 392                if (autocorrect > 0) {
 393                        fprintf_ln(stderr, _("in %0.1f seconds automatically..."),
 394                                (float)autocorrect/10.0);
 395                        sleep_millisec(autocorrect * 100);
 396                }
 397                return assumed;
 398        }
 399
 400        fprintf_ln(stderr, _("git: '%s' is not a git command. See 'git --help'."), cmd);
 401
 402        if (SIMILAR_ENOUGH(best_similarity)) {
 403                fprintf_ln(stderr,
 404                           Q_("\nDid you mean this?",
 405                              "\nDid you mean one of these?",
 406                           n));
 407
 408                for (i = 0; i < n; i++)
 409                        fprintf(stderr, "\t%s\n", main_cmds.names[i]->name);
 410        }
 411
 412        exit(1);
 413}
 414
 415int cmd_version(int argc, const char **argv, const char *prefix)
 416{
 417        /*
 418         * The format of this string should be kept stable for compatibility
 419         * with external projects that rely on the output of "git version".
 420         */
 421        printf("git version %s\n", git_version_string);
 422        while (*++argv) {
 423                if (!strcmp(*argv, "--build-options")) {
 424                        printf("sizeof-long: %d\n", (int)sizeof(long));
 425                        /* NEEDSWORK: also save and output GIT-BUILD_OPTIONS? */
 426                }
 427        }
 428        return 0;
 429}
 430
 431struct similar_ref_cb {
 432        const char *base_ref;
 433        struct string_list *similar_refs;
 434};
 435
 436static int append_similar_ref(const char *refname, const struct object_id *oid,
 437                              int flags, void *cb_data)
 438{
 439        struct similar_ref_cb *cb = (struct similar_ref_cb *)(cb_data);
 440        char *branch = strrchr(refname, '/') + 1;
 441        const char *remote;
 442
 443        /* A remote branch of the same name is deemed similar */
 444        if (skip_prefix(refname, "refs/remotes/", &remote) &&
 445            !strcmp(branch, cb->base_ref))
 446                string_list_append(cb->similar_refs, remote);
 447        return 0;
 448}
 449
 450static struct string_list guess_refs(const char *ref)
 451{
 452        struct similar_ref_cb ref_cb;
 453        struct string_list similar_refs = STRING_LIST_INIT_NODUP;
 454
 455        ref_cb.base_ref = ref;
 456        ref_cb.similar_refs = &similar_refs;
 457        for_each_ref(append_similar_ref, &ref_cb);
 458        return similar_refs;
 459}
 460
 461void help_unknown_ref(const char *ref, const char *cmd, const char *error)
 462{
 463        int i;
 464        struct string_list suggested_refs = guess_refs(ref);
 465
 466        fprintf_ln(stderr, _("%s: %s - %s"), cmd, ref, error);
 467
 468        if (suggested_refs.nr > 0) {
 469                fprintf_ln(stderr,
 470                           Q_("\nDid you mean this?",
 471                              "\nDid you mean one of these?",
 472                              suggested_refs.nr));
 473                for (i = 0; i < suggested_refs.nr; i++)
 474                        fprintf(stderr, "\t%s\n", suggested_refs.items[i].string);
 475        }
 476
 477        string_list_clear(&suggested_refs, 0);
 478        exit(1);
 479}