help.con commit builtin/blame.c: struct blame_entry does not need a prev link (a0f58c5)
   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 = xmalloc(sizeof(*ent) + len + 1);
  15
  16        ent->len = len;
  17        memcpy(ent->name, name, len);
  18        ent->name[len] = 0;
  19
  20        ALLOC_GROW(cmds->names, cmds->cnt + 1, cmds->alloc);
  21        cmds->names[cmds->cnt++] = ent;
  22}
  23
  24static void clean_cmdnames(struct cmdnames *cmds)
  25{
  26        int i;
  27        for (i = 0; i < cmds->cnt; ++i)
  28                free(cmds->names[i]);
  29        free(cmds->names);
  30        cmds->cnt = 0;
  31        cmds->alloc = 0;
  32}
  33
  34static int cmdname_compare(const void *a_, const void *b_)
  35{
  36        struct cmdname *a = *(struct cmdname **)a_;
  37        struct cmdname *b = *(struct cmdname **)b_;
  38        return strcmp(a->name, b->name);
  39}
  40
  41static void uniq(struct cmdnames *cmds)
  42{
  43        int i, j;
  44
  45        if (!cmds->cnt)
  46                return;
  47
  48        for (i = j = 1; i < cmds->cnt; i++) {
  49                if (!strcmp(cmds->names[i]->name, cmds->names[j-1]->name))
  50                        free(cmds->names[i]);
  51                else
  52                        cmds->names[j++] = cmds->names[i];
  53        }
  54
  55        cmds->cnt = j;
  56}
  57
  58void exclude_cmds(struct cmdnames *cmds, struct cmdnames *excludes)
  59{
  60        int ci, cj, ei;
  61        int cmp;
  62
  63        ci = cj = ei = 0;
  64        while (ci < cmds->cnt && ei < excludes->cnt) {
  65                cmp = strcmp(cmds->names[ci]->name, excludes->names[ei]->name);
  66                if (cmp < 0)
  67                        cmds->names[cj++] = cmds->names[ci++];
  68                else if (cmp == 0) {
  69                        ei++;
  70                        free(cmds->names[ci++]);
  71                } else if (cmp > 0)
  72                        ei++;
  73        }
  74
  75        while (ci < cmds->cnt)
  76                cmds->names[cj++] = cmds->names[ci++];
  77
  78        cmds->cnt = cj;
  79}
  80
  81static void pretty_print_string_list(struct cmdnames *cmds,
  82                                     unsigned int colopts)
  83{
  84        struct string_list list = STRING_LIST_INIT_NODUP;
  85        struct column_options copts;
  86        int i;
  87
  88        for (i = 0; i < cmds->cnt; i++)
  89                string_list_append(&list, cmds->names[i]->name);
  90        /*
  91         * always enable column display, we only consult column.*
  92         * about layout strategy and stuff
  93         */
  94        colopts = (colopts & ~COL_ENABLE_MASK) | COL_ENABLED;
  95        memset(&copts, 0, sizeof(copts));
  96        copts.indent = "  ";
  97        copts.padding = 2;
  98        print_columns(&list, colopts, &copts);
  99        string_list_clear(&list, 0);
 100}
 101
 102static int is_executable(const char *name)
 103{
 104        struct stat st;
 105
 106        if (stat(name, &st) || /* stat, not lstat */
 107            !S_ISREG(st.st_mode))
 108                return 0;
 109
 110#if defined(GIT_WINDOWS_NATIVE)
 111{       /* cannot trust the executable bit, peek into the file instead */
 112        char buf[3] = { 0 };
 113        int n;
 114        int fd = open(name, O_RDONLY);
 115        st.st_mode &= ~S_IXUSR;
 116        if (fd >= 0) {
 117                n = read(fd, buf, 2);
 118                if (n == 2)
 119                        /* DOS executables start with "MZ" */
 120                        if (!strcmp(buf, "#!") || !strcmp(buf, "MZ"))
 121                                st.st_mode |= S_IXUSR;
 122                close(fd);
 123        }
 124}
 125#endif
 126        return st.st_mode & S_IXUSR;
 127}
 128
 129static void list_commands_in_dir(struct cmdnames *cmds,
 130                                         const char *path,
 131                                         const char *prefix)
 132{
 133        int prefix_len;
 134        DIR *dir = opendir(path);
 135        struct dirent *de;
 136        struct strbuf buf = STRBUF_INIT;
 137        int len;
 138
 139        if (!dir)
 140                return;
 141        if (!prefix)
 142                prefix = "git-";
 143        prefix_len = strlen(prefix);
 144
 145        strbuf_addf(&buf, "%s/", path);
 146        len = buf.len;
 147
 148        while ((de = readdir(dir)) != NULL) {
 149                int entlen;
 150
 151                if (!starts_with(de->d_name, prefix))
 152                        continue;
 153
 154                strbuf_setlen(&buf, len);
 155                strbuf_addstr(&buf, de->d_name);
 156                if (!is_executable(buf.buf))
 157                        continue;
 158
 159                entlen = strlen(de->d_name) - prefix_len;
 160                if (has_extension(de->d_name, ".exe"))
 161                        entlen -= 4;
 162
 163                add_cmdname(cmds, de->d_name + prefix_len, entlen);
 164        }
 165        closedir(dir);
 166        strbuf_release(&buf);
 167}
 168
 169void load_command_list(const char *prefix,
 170                struct cmdnames *main_cmds,
 171                struct cmdnames *other_cmds)
 172{
 173        const char *env_path = getenv("PATH");
 174        const char *exec_path = git_exec_path();
 175
 176        if (exec_path) {
 177                list_commands_in_dir(main_cmds, exec_path, prefix);
 178                qsort(main_cmds->names, main_cmds->cnt,
 179                      sizeof(*main_cmds->names), cmdname_compare);
 180                uniq(main_cmds);
 181        }
 182
 183        if (env_path) {
 184                char *paths, *path, *colon;
 185                path = paths = xstrdup(env_path);
 186                while (1) {
 187                        if ((colon = strchr(path, PATH_SEP)))
 188                                *colon = 0;
 189                        if (!exec_path || strcmp(path, exec_path))
 190                                list_commands_in_dir(other_cmds, path, prefix);
 191
 192                        if (!colon)
 193                                break;
 194                        path = colon + 1;
 195                }
 196                free(paths);
 197
 198                qsort(other_cmds->names, other_cmds->cnt,
 199                      sizeof(*other_cmds->names), cmdname_compare);
 200                uniq(other_cmds);
 201        }
 202        exclude_cmds(other_cmds, main_cmds);
 203}
 204
 205void list_commands(unsigned int colopts,
 206                   struct cmdnames *main_cmds, struct cmdnames *other_cmds)
 207{
 208        if (main_cmds->cnt) {
 209                const char *exec_path = git_exec_path();
 210                printf_ln(_("available git commands in '%s'"), exec_path);
 211                putchar('\n');
 212                pretty_print_string_list(main_cmds, colopts);
 213                putchar('\n');
 214        }
 215
 216        if (other_cmds->cnt) {
 217                printf_ln(_("git commands available from elsewhere on your $PATH"));
 218                putchar('\n');
 219                pretty_print_string_list(other_cmds, colopts);
 220                putchar('\n');
 221        }
 222}
 223
 224void list_common_cmds_help(void)
 225{
 226        int i, longest = 0;
 227
 228        for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
 229                if (longest < strlen(common_cmds[i].name))
 230                        longest = strlen(common_cmds[i].name);
 231        }
 232
 233        puts(_("The most commonly used git commands are:"));
 234        for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
 235                printf("   %s   ", common_cmds[i].name);
 236                mput_char(' ', longest - strlen(common_cmds[i].name));
 237                puts(_(common_cmds[i].help));
 238        }
 239}
 240
 241int is_in_cmdlist(struct cmdnames *c, const char *s)
 242{
 243        int i;
 244        for (i = 0; i < c->cnt; i++)
 245                if (!strcmp(s, c->names[i]->name))
 246                        return 1;
 247        return 0;
 248}
 249
 250static int autocorrect;
 251static struct cmdnames aliases;
 252
 253static int git_unknown_cmd_config(const char *var, const char *value, void *cb)
 254{
 255        if (!strcmp(var, "help.autocorrect"))
 256                autocorrect = git_config_int(var,value);
 257        /* Also use aliases for command lookup */
 258        if (starts_with(var, "alias."))
 259                add_cmdname(&aliases, var + 6, strlen(var + 6));
 260
 261        return git_default_config(var, value, cb);
 262}
 263
 264static int levenshtein_compare(const void *p1, const void *p2)
 265{
 266        const struct cmdname *const *c1 = p1, *const *c2 = p2;
 267        const char *s1 = (*c1)->name, *s2 = (*c2)->name;
 268        int l1 = (*c1)->len;
 269        int l2 = (*c2)->len;
 270        return l1 != l2 ? l1 - l2 : strcmp(s1, s2);
 271}
 272
 273static void add_cmd_list(struct cmdnames *cmds, struct cmdnames *old)
 274{
 275        int i;
 276        ALLOC_GROW(cmds->names, cmds->cnt + old->cnt, cmds->alloc);
 277
 278        for (i = 0; i < old->cnt; i++)
 279                cmds->names[cmds->cnt++] = old->names[i];
 280        free(old->names);
 281        old->cnt = 0;
 282        old->names = NULL;
 283}
 284
 285/* An empirically derived magic number */
 286#define SIMILARITY_FLOOR 7
 287#define SIMILAR_ENOUGH(x) ((x) < SIMILARITY_FLOOR)
 288
 289static const char bad_interpreter_advice[] =
 290        N_("'%s' appears to be a git command, but we were not\n"
 291        "able to execute it. Maybe git-%s is broken?");
 292
 293const char *help_unknown_cmd(const char *cmd)
 294{
 295        int i, n, best_similarity = 0;
 296        struct cmdnames main_cmds, other_cmds;
 297
 298        memset(&main_cmds, 0, sizeof(main_cmds));
 299        memset(&other_cmds, 0, sizeof(other_cmds));
 300        memset(&aliases, 0, sizeof(aliases));
 301
 302        git_config(git_unknown_cmd_config, NULL);
 303
 304        load_command_list("git-", &main_cmds, &other_cmds);
 305
 306        add_cmd_list(&main_cmds, &aliases);
 307        add_cmd_list(&main_cmds, &other_cmds);
 308        qsort(main_cmds.names, main_cmds.cnt,
 309              sizeof(main_cmds.names), cmdname_compare);
 310        uniq(&main_cmds);
 311
 312        /* This abuses cmdname->len for levenshtein distance */
 313        for (i = 0, n = 0; i < main_cmds.cnt; i++) {
 314                int cmp = 0; /* avoid compiler stupidity */
 315                const char *candidate = main_cmds.names[i]->name;
 316
 317                /*
 318                 * An exact match means we have the command, but
 319                 * for some reason exec'ing it gave us ENOENT; probably
 320                 * it's a bad interpreter in the #! line.
 321                 */
 322                if (!strcmp(candidate, cmd))
 323                        die(_(bad_interpreter_advice), cmd, cmd);
 324
 325                /* Does the candidate appear in common_cmds list? */
 326                while (n < ARRAY_SIZE(common_cmds) &&
 327                       (cmp = strcmp(common_cmds[n].name, candidate)) < 0)
 328                        n++;
 329                if ((n < ARRAY_SIZE(common_cmds)) && !cmp) {
 330                        /* Yes, this is one of the common commands */
 331                        n++; /* use the entry from common_cmds[] */
 332                        if (starts_with(candidate, cmd)) {
 333                                /* Give prefix match a very good score */
 334                                main_cmds.names[i]->len = 0;
 335                                continue;
 336                        }
 337                }
 338
 339                main_cmds.names[i]->len =
 340                        levenshtein(cmd, candidate, 0, 2, 1, 3) + 1;
 341        }
 342
 343        qsort(main_cmds.names, main_cmds.cnt,
 344              sizeof(*main_cmds.names), levenshtein_compare);
 345
 346        if (!main_cmds.cnt)
 347                die(_("Uh oh. Your system reports no Git commands at all."));
 348
 349        /* skip and count prefix matches */
 350        for (n = 0; n < main_cmds.cnt && !main_cmds.names[n]->len; n++)
 351                ; /* still counting */
 352
 353        if (main_cmds.cnt <= n) {
 354                /* prefix matches with everything? that is too ambiguous */
 355                best_similarity = SIMILARITY_FLOOR + 1;
 356        } else {
 357                /* count all the most similar ones */
 358                for (best_similarity = main_cmds.names[n++]->len;
 359                     (n < main_cmds.cnt &&
 360                      best_similarity == main_cmds.names[n]->len);
 361                     n++)
 362                        ; /* still counting */
 363        }
 364        if (autocorrect && n == 1 && SIMILAR_ENOUGH(best_similarity)) {
 365                const char *assumed = main_cmds.names[0]->name;
 366                main_cmds.names[0] = NULL;
 367                clean_cmdnames(&main_cmds);
 368                fprintf_ln(stderr,
 369                           _("WARNING: You called a Git command named '%s', "
 370                             "which does not exist.\n"
 371                             "Continuing under the assumption that you meant '%s'"),
 372                        cmd, assumed);
 373                if (autocorrect > 0) {
 374                        fprintf_ln(stderr, _("in %0.1f seconds automatically..."),
 375                                (float)autocorrect/10.0);
 376                        poll(NULL, 0, autocorrect * 100);
 377                }
 378                return assumed;
 379        }
 380
 381        fprintf_ln(stderr, _("git: '%s' is not a git command. See 'git --help'."), cmd);
 382
 383        if (SIMILAR_ENOUGH(best_similarity)) {
 384                fprintf_ln(stderr,
 385                           Q_("\nDid you mean this?",
 386                              "\nDid you mean one of these?",
 387                           n));
 388
 389                for (i = 0; i < n; i++)
 390                        fprintf(stderr, "\t%s\n", main_cmds.names[i]->name);
 391        }
 392
 393        exit(1);
 394}
 395
 396int cmd_version(int argc, const char **argv, const char *prefix)
 397{
 398        /*
 399         * The format of this string should be kept stable for compatibility
 400         * with external projects that rely on the output of "git version".
 401         */
 402        printf("git version %s\n", git_version_string);
 403        return 0;
 404}
 405
 406struct similar_ref_cb {
 407        const char *base_ref;
 408        struct string_list *similar_refs;
 409};
 410
 411static int append_similar_ref(const char *refname, const unsigned char *sha1,
 412                              int flags, void *cb_data)
 413{
 414        struct similar_ref_cb *cb = (struct similar_ref_cb *)(cb_data);
 415        char *branch = strrchr(refname, '/') + 1;
 416        /* A remote branch of the same name is deemed similar */
 417        if (starts_with(refname, "refs/remotes/") &&
 418            !strcmp(branch, cb->base_ref))
 419                string_list_append(cb->similar_refs,
 420                                   refname + strlen("refs/remotes/"));
 421        return 0;
 422}
 423
 424static struct string_list guess_refs(const char *ref)
 425{
 426        struct similar_ref_cb ref_cb;
 427        struct string_list similar_refs = STRING_LIST_INIT_NODUP;
 428
 429        ref_cb.base_ref = ref;
 430        ref_cb.similar_refs = &similar_refs;
 431        for_each_ref(append_similar_ref, &ref_cb);
 432        return similar_refs;
 433}
 434
 435void help_unknown_ref(const char *ref, const char *cmd, const char *error)
 436{
 437        int i;
 438        struct string_list suggested_refs = guess_refs(ref);
 439
 440        fprintf_ln(stderr, _("%s: %s - %s"), cmd, ref, error);
 441
 442        if (suggested_refs.nr > 0) {
 443                fprintf_ln(stderr,
 444                           Q_("\nDid you mean this?",
 445                              "\nDid you mean one of these?",
 446                              suggested_refs.nr));
 447                for (i = 0; i < suggested_refs.nr; i++)
 448                        fprintf(stderr, "\t%s\n", suggested_refs.items[i].string);
 449        }
 450
 451        string_list_clear(&suggested_refs, 0);
 452        exit(1);
 453}