help.c

   1 #include "cache.h"
   2 #include "builtin.h"
   3 #include "exec_cmd.h"
   4 #include "help.h"
   5
   6 /* most GUI terminals set COLUMNS (although some don't export it) */
   7 static int term_columns(void)
   8 {
   9         char *col_string = getenv("COLUMNS");
  10         int n_cols;
  11
  12         if (col_string && (n_cols = atoi(col_string)) > 0)
  13                 return n_cols;
  14
  15 #ifdef TIOCGWINSZ
  16         {
  17                 struct winsize ws;
  18                 if (!ioctl(1, TIOCGWINSZ, &ws)) {
  19                         if (ws.ws_col)
  20                                 return ws.ws_col;
  21                 }
  22         }
  23 #endif
  24
  25         return 80;
  26 }
  27
  28 void add_cmdname(struct cmdnames *cmds, const char *name, int len)
  29 {
  30         struct cmdname *ent = xmalloc(sizeof(*ent) + len + 1);
  31
  32         ent->len = len;
  33         memcpy(ent->name, name, len);
  34         ent->name[len] = 0;
  35
  36         ALLOC_GROW(cmds->names, cmds->cnt + 1, cmds->alloc);
  37         cmds->names[cmds->cnt++] = ent;
  38 }
  39
  40 static int cmdname_compare(const void *a_, const void *b_)
  41 {
  42         struct cmdname *a = *(struct cmdname **)a_;
  43         struct cmdname *b = *(struct cmdname **)b_;
  44         return strcmp(a->name, b->name);
  45 }
  46
  47 static void uniq(struct cmdnames *cmds)
  48 {
  49         int i, j;
  50
  51         if (!cmds->cnt)
  52                 return;
  53
  54         for (i = j = 1; i < cmds->cnt; i++)
  55                 if (strcmp(cmds->names[i]->name, cmds->names[i-1]->name))
  56                         cmds->names[j++] = cmds->names[i];
  57
  58         cmds->cnt = j;
  59 }
  60
  61 void exclude_cmds(struct cmdnames *cmds, struct cmdnames *excludes)
  62 {
  63         int ci, cj, ei;
  64         int cmp;
  65
  66         ci = cj = ei = 0;
  67         while (ci < cmds->cnt && ei < excludes->cnt) {
  68                 cmp = strcmp(cmds->names[ci]->name, excludes->names[ei]->name);
  69                 if (cmp < 0)
  70                         cmds->names[cj++] = cmds->names[ci++];
  71                 else if (cmp == 0)
  72                         ci++, ei++;
  73                 else if (cmp > 0)
  74                         ei++;
  75         }
  76
  77         while (ci < cmds->cnt)
  78                 cmds->names[cj++] = cmds->names[ci++];
  79
  80         cmds->cnt = cj;
  81 }
  82
  83 static void pretty_print_string_list(struct cmdnames *cmds, int longest)
  84 {
  85         int cols = 1, rows;
  86         int space = longest + 1; /* min 1 SP between words */
  87         int max_cols = term_columns() - 1; /* don't print *on* the edge */
  88         int i, j;
  89
  90         if (space < max_cols)
  91                 cols = max_cols / space;
  92         rows = (cmds->cnt + cols - 1) / cols;
  93
  94         for (i = 0; i < rows; i++) {
  95                 printf("  ");
  96
  97                 for (j = 0; j < cols; j++) {
  98                         int n = j * rows + i;
  99                         int size = space;
 100                         if (n >= cmds->cnt)
 101                                 break;
 102                         if (j == cols-1 || n + rows >= cmds->cnt)
 103                                 size = 1;
 104                         printf("%-*s", size, cmds->names[n]->name);
 105                 }
 106                 putchar('\n');
 107         }
 108 }
 109
 110 static int is_executable(const char *name)
 111 {
 112         struct stat st;
 113
 114         if (stat(name, &st) || /* stat, not lstat */
 115             !S_ISREG(st.st_mode))
 116                 return 0;
 117
 118 #ifdef __MINGW32__
 119         /* cannot trust the executable bit, peek into the file instead */
 120         char buf[3] = { 0 };
 121         int n;
 122         int fd = open(name, O_RDONLY);
 123         st.st_mode &= ~S_IXUSR;
 124         if (fd >= 0) {
 125                 n = read(fd, buf, 2);
 126                 if (n == 2)
 127                         /* DOS executables start with "MZ" */
 128                         if (!strcmp(buf, "#!") || !strcmp(buf, "MZ"))
 129                                 st.st_mode |= S_IXUSR;
 130                 close(fd);
 131         }
 132 #endif
 133         return st.st_mode & S_IXUSR;
 134 }
 135
 136 static unsigned int list_commands_in_dir(struct cmdnames *cmds,
 137                                          const char *path,
 138                                          const char *prefix)
 139 {
 140         unsigned int longest = 0;
 141         int prefix_len;
 142         DIR *dir = opendir(path);
 143         struct dirent *de;
 144         struct strbuf buf = STRBUF_INIT;
 145         int len;
 146
 147         if (!dir)
 148                 return 0;
 149         if (!prefix)
 150                 prefix = "git-";
 151         prefix_len = strlen(prefix);
 152
 153         strbuf_addf(&buf, "%s/", path);
 154         len = buf.len;
 155
 156         while ((de = readdir(dir)) != NULL) {
 157                 int entlen;
 158
 159                 if (prefixcmp(de->d_name, prefix))
 160                         continue;
 161
 162                 strbuf_setlen(&buf, len);
 163                 strbuf_addstr(&buf, de->d_name);
 164                 if (!is_executable(buf.buf))
 165                         continue;
 166
 167                 entlen = strlen(de->d_name) - prefix_len;
 168                 if (has_extension(de->d_name, ".exe"))
 169                         entlen -= 4;
 170
 171                 if (longest < entlen)
 172                         longest = entlen;
 173
 174                 add_cmdname(cmds, de->d_name + prefix_len, entlen);
 175         }
 176         closedir(dir);
 177         strbuf_release(&buf);
 178
 179         return longest;
 180 }
 181
 182 unsigned int load_command_list(const char *prefix,
 183                 struct cmdnames *main_cmds,
 184                 struct cmdnames *other_cmds)
 185 {
 186         unsigned int longest = 0;
 187         unsigned int len;
 188         const char *env_path = getenv("PATH");
 189         char *paths, *path, *colon;
 190         const char *exec_path = git_exec_path();
 191
 192         if (exec_path)
 193                 longest = list_commands_in_dir(main_cmds, exec_path, prefix);
 194
 195         if (!env_path) {
 196                 fprintf(stderr, "PATH not set\n");
 197                 exit(1);
 198         }
 199
 200         path = paths = xstrdup(env_path);
 201         while (1) {
 202                 if ((colon = strchr(path, PATH_SEP)))
 203                         *colon = 0;
 204
 205                 len = list_commands_in_dir(other_cmds, path, prefix);
 206                 if (len > longest)
 207                         longest = len;
 208
 209                 if (!colon)
 210                         break;
 211                 path = colon + 1;
 212         }
 213         free(paths);
 214
 215         qsort(main_cmds->names, main_cmds->cnt,
 216               sizeof(*main_cmds->names), cmdname_compare);
 217         uniq(main_cmds);
 218
 219         qsort(other_cmds->names, other_cmds->cnt,
 220               sizeof(*other_cmds->names), cmdname_compare);
 221         uniq(other_cmds);
 222         exclude_cmds(other_cmds, main_cmds);
 223
 224         return longest;
 225 }
 226
 227 void list_commands(const char *title, unsigned int longest,
 228                 struct cmdnames *main_cmds, struct cmdnames *other_cmds)
 229 {
 230         const char *exec_path = git_exec_path();
 231
 232         if (main_cmds->cnt) {
 233                 printf("available %s in '%s'\n", title, exec_path);
 234                 printf("----------------");
 235                 mput_char('-', strlen(title) + strlen(exec_path));
 236                 putchar('\n');
 237                 pretty_print_string_list(main_cmds, longest);
 238                 putchar('\n');
 239         }
 240
 241         if (other_cmds->cnt) {
 242                 printf("%s available from elsewhere on your $PATH\n", title);
 243                 printf("---------------------------------------");
 244                 mput_char('-', strlen(title));
 245                 putchar('\n');
 246                 pretty_print_string_list(other_cmds, longest);
 247                 putchar('\n');
 248         }
 249 }
 250
 251 int is_in_cmdlist(struct cmdnames *c, const char *s)
 252 {
 253         int i;
 254         for (i = 0; i < c->cnt; i++)
 255                 if (!strcmp(s, c->names[i]->name))
 256                         return 1;
 257         return 0;
 258 }
 259
 260 void help_unknown_cmd(const char *cmd)
 261 {
 262         fprintf(stderr, "git: '%s' is not a git-command. See 'git --help'.\n", cmd);
 263         exit(1);
 264 }
 265
 266 int cmd_version(int argc, const char **argv, const char *prefix)
 267 {
 268         printf("git version %s\n", git_version_string);
 269         return 0;
 270 }