Andrew's git - gitweb.git/blob

   1#include <stdio.h>
   2#include <sys/types.h>
   3#include <sys/stat.h>
   4#include <dirent.h>
   5#include <unistd.h>
   6#include <stdlib.h>
   7#include <string.h>
   8#include <errno.h>
   9#include <limits.h>
  10#include <stdarg.h>
  11#include <sys/ioctl.h>
  12#include "git-compat-util.h"
  13#include "exec_cmd.h"
  14
  15#ifndef PATH_MAX
  16# define PATH_MAX 4096
  17#endif
  18
  19static const char git_usage[] =
  20        "Usage: git [--version] [--exec-path[=GIT_EXEC_PATH]] [--help] COMMAND [ ARGS ]";
  21
  22/* most gui terms set COLUMNS (although some don't export it) */
  23static int term_columns(void)
  24{
  25        char *col_string = getenv("COLUMNS");
  26        int n_cols = 0;
  27
  28        if (col_string && (n_cols = atoi(col_string)) > 0)
  29                return n_cols;
  30
  31#ifdef TIOCGWINSZ
  32        {
  33                struct winsize ws;
  34                if (!ioctl(1, TIOCGWINSZ, &ws)) {
  35                        if (ws.ws_col)
  36                                return ws.ws_col;
  37                }
  38        }
  39#endif
  40
  41        return 80;
  42}
  43
  44static void oom(void)
  45{
  46        fprintf(stderr, "git: out of memory\n");
  47        exit(1);
  48}
  49
  50static inline void mput_char(char c, unsigned int num)
  51{
  52        while(num--)
  53                putchar(c);
  54}
  55
  56static struct cmdname {
  57        size_t len;
  58        char name[1];
  59} **cmdname;
  60static int cmdname_alloc, cmdname_cnt;
  61
  62static void add_cmdname(const char *name, int len)
  63{
  64        struct cmdname *ent;
  65        if (cmdname_alloc <= cmdname_cnt) {
  66                cmdname_alloc = cmdname_alloc + 200;
  67                cmdname = realloc(cmdname, cmdname_alloc * sizeof(*cmdname));
  68                if (!cmdname)
  69                        oom();
  70        }
  71        ent = malloc(sizeof(*ent) + len);
  72        if (!ent)
  73                oom();
  74        ent->len = len;
  75        memcpy(ent->name, name, len);
  76        ent->name[len] = 0;
  77        cmdname[cmdname_cnt++] = ent;
  78}
  79
  80static int cmdname_compare(const void *a_, const void *b_)
  81{
  82        struct cmdname *a = *(struct cmdname **)a_;
  83        struct cmdname *b = *(struct cmdname **)b_;
  84        return strcmp(a->name, b->name);
  85}
  86
  87static void pretty_print_string_list(struct cmdname **cmdname, int longest)
  88{
  89        int cols = 1, rows;
  90        int space = longest + 1; /* min 1 SP between words */
  91        int max_cols = term_columns() - 1; /* don't print *on* the edge */
  92        int i, j;
  93
  94        if (space < max_cols)
  95                cols = max_cols / space;
  96        rows = (cmdname_cnt + cols - 1) / cols;
  97
  98        qsort(cmdname, cmdname_cnt, sizeof(*cmdname), cmdname_compare);
  99
 100        for (i = 0; i < rows; i++) {
 101                printf("  ");
 102
 103                for (j = 0; j < cols; j++) {
 104                        int n = j * rows + i;
 105                        int size = space;
 106                        if (n >= cmdname_cnt)
 107                                break;
 108                        if (j == cols-1 || n + rows >= cmdname_cnt)
 109                                size = 1;
 110                        printf("%-*s", size, cmdname[n]->name);
 111                }
 112                putchar('\n');
 113        }
 114}
 115
 116static void list_commands(const char *exec_path, const char *pattern)
 117{
 118        unsigned int longest = 0;
 119        char path[PATH_MAX];
 120        int dirlen;
 121        DIR *dir = opendir(exec_path);
 122        struct dirent *de;
 123
 124        if (!dir) {
 125                fprintf(stderr, "git: '%s': %s\n", exec_path, strerror(errno));
 126                exit(1);
 127        }
 128
 129        dirlen = strlen(exec_path);
 130        if (PATH_MAX - 20 < dirlen) {
 131                fprintf(stderr, "git: insanely long exec-path '%s'\n",
 132                        exec_path);
 133                exit(1);
 134        }
 135
 136        memcpy(path, exec_path, dirlen);
 137        path[dirlen++] = '/';
 138
 139        while ((de = readdir(dir)) != NULL) {
 140                struct stat st;
 141                int entlen;
 142
 143                if (strncmp(de->d_name, "git-", 4))
 144                        continue;
 145                strcpy(path+dirlen, de->d_name);
 146                if (stat(path, &st) || /* stat, not lstat */
 147                    !S_ISREG(st.st_mode) ||
 148                    !(st.st_mode & S_IXUSR))
 149                        continue;
 150
 151                entlen = strlen(de->d_name);
 152                if (4 < entlen && !strcmp(de->d_name + entlen - 4, ".exe"))
 153                        entlen -= 4;
 154
 155                if (longest < entlen)
 156                        longest = entlen;
 157
 158                add_cmdname(de->d_name + 4, entlen-4);
 159        }
 160        closedir(dir);
 161
 162        printf("git commands available in '%s'\n", exec_path);
 163        printf("----------------------------");
 164        mput_char('-', strlen(exec_path));
 165        putchar('\n');
 166        pretty_print_string_list(cmdname, longest - 4);
 167        putchar('\n');
 168}
 169
 170#ifdef __GNUC__
 171static void cmd_usage(const char *exec_path, const char *fmt, ...)
 172        __attribute__((__format__(__printf__, 2, 3), __noreturn__));
 173#endif
 174static void cmd_usage(const char *exec_path, const char *fmt, ...)
 175{
 176        if (fmt) {
 177                va_list ap;
 178
 179                va_start(ap, fmt);
 180                printf("git: ");
 181                vprintf(fmt, ap);
 182                va_end(ap);
 183                putchar('\n');
 184        }
 185        else
 186                puts(git_usage);
 187
 188        putchar('\n');
 189
 190        if(exec_path)
 191                list_commands(exec_path, "git-*");
 192
 193        exit(1);
 194}
 195
 196static void prepend_to_path(const char *dir, int len)
 197{
 198        char *path, *old_path = getenv("PATH");
 199        int path_len = len;
 200
 201        if (!old_path)
 202                old_path = "/usr/local/bin:/usr/bin:/bin";
 203
 204        path_len = len + strlen(old_path) + 1;
 205
 206        path = malloc(path_len + 1);
 207
 208        memcpy(path, dir, len);
 209        path[len] = ':';
 210        memcpy(path + len + 1, old_path, path_len - len);
 211
 212        setenv("PATH", path, 1);
 213}
 214
 215static void show_man_page(char *git_cmd)
 216{
 217        char *page;
 218
 219        if (!strncmp(git_cmd, "git", 3))
 220                page = git_cmd;
 221        else {
 222                int page_len = strlen(git_cmd) + 4;
 223
 224                page = malloc(page_len + 1);
 225                strcpy(page, "git-");
 226                strcpy(page + 4, git_cmd);
 227                page[page_len] = 0;
 228        }
 229
 230        execlp("man", "man", page, NULL);
 231}
 232
 233int main(int argc, char **argv, char **envp)
 234{
 235        char git_command[PATH_MAX + 1];
 236        char wd[PATH_MAX + 1];
 237        int i, show_help = 0;
 238        const char *exec_path;
 239
 240        getcwd(wd, PATH_MAX);
 241
 242        for (i = 1; i < argc; i++) {
 243                char *arg = argv[i];
 244
 245                if (!strcmp(arg, "help")) {
 246                        show_help = 1;
 247                        continue;
 248                }
 249
 250                if (strncmp(arg, "--", 2))
 251                        break;
 252
 253                arg += 2;
 254
 255                if (!strncmp(arg, "exec-path", 9)) {
 256                        arg += 9;
 257                        if (*arg == '=') {
 258                                exec_path = arg + 1;
 259                                git_set_exec_path(exec_path);
 260                        } else {
 261                                puts(git_exec_path());
 262                                exit(0);
 263                        }
 264                }
 265                else if (!strcmp(arg, "version")) {
 266                        printf("git version %s\n", GIT_VERSION);
 267                        exit(0);
 268                }
 269                else if (!strcmp(arg, "help"))
 270                        show_help = 1;
 271                else if (!show_help)
 272                        cmd_usage(NULL, NULL);
 273        }
 274
 275        if (i >= argc || show_help) {
 276                if (i >= argc)
 277                        cmd_usage(git_exec_path(), NULL);
 278
 279                show_man_page(argv[i]);
 280        }
 281
 282        exec_path = git_exec_path();
 283        prepend_to_path(exec_path, strlen(exec_path));
 284
 285        execv_git_cmd(argv + i);
 286
 287        if (errno == ENOENT)
 288                cmd_usage(exec_path, "'%s' is not a git-command", argv[i]);
 289
 290        fprintf(stderr, "Failed to run command '%s': %s\n",
 291                git_command, strerror(errno));
 292
 293        return 1;
 294}