auto-detect changed prefix and/or changed build flags
[gitweb.git] / git.c
diff --git a/git.c b/git.c
index 993cd0d4904be11edb6234e47d10376733928740..329ebec78cd057a14a22cca2e89a9cb09a53f5dd 100644 (file)
--- a/git.c
+++ b/git.c
 #include <errno.h>
 #include <limits.h>
 #include <stdarg.h>
-#include <sys/ioctl.h>
 #include "git-compat-util.h"
 #include "exec_cmd.h"
+#include "cache.h"
 
-#ifndef PATH_MAX
-# define PATH_MAX 4096
-#endif
+#include "builtin.h"
 
-static const char git_usage[] =
-       "Usage: git [--version] [--exec-path[=GIT_EXEC_PATH]] [--help] COMMAND [ ARGS ]";
-
-/* most gui terms set COLUMNS (although some don't export it) */
-static int term_columns(void)
+static void prepend_to_path(const char *dir, int len)
 {
-       char *col_string = getenv("COLUMNS");
-       int n_cols = 0;
-
-       if (col_string && (n_cols = atoi(col_string)) > 0)
-               return n_cols;
-
-#ifdef TIOCGWINSZ
-       {
-               struct winsize ws;
-               if (!ioctl(1, TIOCGWINSZ, &ws)) {
-                       if (ws.ws_col)
-                               return ws.ws_col;
-               }
-       }
-#endif
+       char *path, *old_path = getenv("PATH");
+       int path_len = len;
 
-       return 80;
-}
+       if (!old_path)
+               old_path = "/usr/local/bin:/usr/bin:/bin";
 
-static void oom(void)
-{
-       fprintf(stderr, "git: out of memory\n");
-       exit(1);
-}
+       path_len = len + strlen(old_path) + 1;
 
-static inline void mput_char(char c, unsigned int num)
-{
-       while(num--)
-               putchar(c);
-}
+       path = malloc(path_len + 1);
 
-static struct cmdname {
-       size_t len;
-       char name[1];
-} **cmdname;
-static int cmdname_alloc, cmdname_cnt;
+       memcpy(path, dir, len);
+       path[len] = ':';
+       memcpy(path + len + 1, old_path, path_len - len);
 
-static void add_cmdname(const char *name, int len)
-{
-       struct cmdname *ent;
-       if (cmdname_alloc <= cmdname_cnt) {
-               cmdname_alloc = cmdname_alloc + 200;
-               cmdname = realloc(cmdname, cmdname_alloc * sizeof(*cmdname));
-               if (!cmdname)
-                       oom();
-       }
-       ent = malloc(sizeof(*ent) + len);
-       if (!ent)
-               oom();
-       ent->len = len;
-       memcpy(ent->name, name, len);
-       ent->name[len] = 0;
-       cmdname[cmdname_cnt++] = ent;
+       setenv("PATH", path, 1);
 }
 
-static int cmdname_compare(const void *a_, const void *b_)
-{
-       struct cmdname *a = *(struct cmdname **)a_;
-       struct cmdname *b = *(struct cmdname **)b_;
-       return strcmp(a->name, b->name);
-}
+static const char *alias_command;
+static char *alias_string = NULL;
 
-static void pretty_print_string_list(struct cmdname **cmdname, int longest)
+static int git_alias_config(const char *var, const char *value)
 {
-       int cols = 1, rows;
-       int space = longest + 1; /* min 1 SP between words */
-       int max_cols = term_columns() - 1; /* don't print *on* the edge */
-       int i, j;
-
-       if (space < max_cols)
-               cols = max_cols / space;
-       rows = (cmdname_cnt + cols - 1) / cols;
-
-       qsort(cmdname, cmdname_cnt, sizeof(*cmdname), cmdname_compare);
-
-       for (i = 0; i < rows; i++) {
-               printf("  ");
-
-               for (j = 0; j < cols; j++) {
-                       int n = j * rows + i;
-                       int size = space;
-                       if (n >= cmdname_cnt)
-                               break;
-                       if (j == cols-1 || n + rows >= cmdname_cnt)
-                               size = 1;
-                       printf("%-*s", size, cmdname[n]->name);
-               }
-               putchar('\n');
+       if (!strncmp(var, "alias.", 6) && !strcmp(var + 6, alias_command)) {
+               alias_string = strdup(value);
        }
+       return 0;
 }
 
-static void list_commands(const char *exec_path, const char *pattern)
+static int split_cmdline(char *cmdline, const char ***argv)
 {
-       unsigned int longest = 0;
-       char path[PATH_MAX];
-       int dirlen;
-       DIR *dir = opendir(exec_path);
-       struct dirent *de;
-
-       if (!dir) {
-               fprintf(stderr, "git: '%s': %s\n", exec_path, strerror(errno));
-               exit(1);
-       }
-
-       dirlen = strlen(exec_path);
-       if (PATH_MAX - 20 < dirlen) {
-               fprintf(stderr, "git: insanely long exec-path '%s'\n",
-                       exec_path);
-               exit(1);
+       int src, dst, count = 0, size = 16;
+       char quoted = 0;
+
+       *argv = malloc(sizeof(char*) * size);
+
+       /* split alias_string */
+       (*argv)[count++] = cmdline;
+       for (src = dst = 0; cmdline[src];) {
+               char c = cmdline[src];
+               if (!quoted && isspace(c)) {
+                       cmdline[dst++] = 0;
+                       while (cmdline[++src]
+                                       && isspace(cmdline[src]))
+                               ; /* skip */
+                       if (count >= size) {
+                               size += 16;
+                               *argv = realloc(*argv, sizeof(char*) * size);
+                       }
+                       (*argv)[count++] = cmdline + dst;
+               } else if(!quoted && (c == '\'' || c == '"')) {
+                       quoted = c;
+                       src++;
+               } else if (c == quoted) {
+                       quoted = 0;
+                       src++;
+               } else {
+                       if (c == '\\' && quoted != '\'') {
+                               src++;
+                               c = cmdline[src];
+                               if (!c) {
+                                       free(*argv);
+                                       *argv = NULL;
+                                       return error("cmdline ends with \\");
+                               }
+                       }
+                       cmdline[dst++] = c;
+                       src++;
+               }
        }
 
-       memcpy(path, exec_path, dirlen);
-       path[dirlen++] = '/';
-
-       while ((de = readdir(dir)) != NULL) {
-               struct stat st;
-               int entlen;
-
-               if (strncmp(de->d_name, "git-", 4))
-                       continue;
-               strcpy(path+dirlen, de->d_name);
-               if (stat(path, &st) || /* stat, not lstat */
-                   !S_ISREG(st.st_mode) ||
-                   !(st.st_mode & S_IXUSR))
-                       continue;
-
-               entlen = strlen(de->d_name);
-               if (4 < entlen && !strcmp(de->d_name + entlen - 4, ".exe"))
-                       entlen -= 4;
-
-               if (longest < entlen)
-                       longest = entlen;
+       cmdline[dst] = 0;
 
-               add_cmdname(de->d_name + 4, entlen-4);
+       if (quoted) {
+               free(*argv);
+               *argv = NULL;
+               return error("unclosed quote");
        }
-       closedir(dir);
-
-       printf("git commands available in '%s'\n", exec_path);
-       printf("----------------------------");
-       mput_char('-', strlen(exec_path));
-       putchar('\n');
-       pretty_print_string_list(cmdname, longest - 4);
-       putchar('\n');
-}
-
-#ifdef __GNUC__
-static void cmd_usage(const char *exec_path, const char *fmt, ...)
-       __attribute__((__format__(__printf__, 2, 3), __noreturn__));
-#endif
-static void cmd_usage(const char *exec_path, const char *fmt, ...)
-{
-       if (fmt) {
-               va_list ap;
-
-               va_start(ap, fmt);
-               printf("git: ");
-               vprintf(fmt, ap);
-               va_end(ap);
-               putchar('\n');
-       }
-       else
-               puts(git_usage);
-
-       putchar('\n');
 
-       if(exec_path)
-               list_commands(exec_path, "git-*");
-
-       exit(1);
+       return count;
 }
 
-static void prepend_to_path(const char *dir, int len)
+static int handle_alias(int *argcp, const char ***argv)
 {
-       char *path, *old_path = getenv("PATH");
-       int path_len = len;
+       int nongit = 0, ret = 0;
+       const char *subdir;
 
-       if (!old_path)
-               old_path = "/usr/local/bin:/usr/bin:/bin";
+       subdir = setup_git_directory_gently(&nongit);
+       if (!nongit) {
+               int count;
+               const char** new_argv;
 
-       path_len = len + strlen(old_path) + 1;
+               alias_command = (*argv)[0];
+               git_config(git_alias_config);
+               if (alias_string) {
 
-       path = malloc(path_len + 1);
+                       count = split_cmdline(alias_string, &new_argv);
 
-       memcpy(path, dir, len);
-       path[len] = ':';
-       memcpy(path + len + 1, old_path, path_len - len);
+                       if (count < 1)
+                               die("empty alias for %s", alias_command);
 
-       setenv("PATH", path, 1);
-}
+                       if (!strcmp(alias_command, new_argv[0]))
+                               die("recursive alias: %s", alias_command);
 
-static void show_man_page(char *git_cmd)
-{
-       char *page;
+                       /* insert after command name */
+                       if (*argcp > 1) {
+                               new_argv = realloc(new_argv, sizeof(char*) *
+                                                  (count + *argcp));
+                               memcpy(new_argv + count, *argv + 1,
+                                      sizeof(char*) * *argcp);
+                       }
 
-       if (!strncmp(git_cmd, "git", 3))
-               page = git_cmd;
-       else {
-               int page_len = strlen(git_cmd) + 4;
+                       *argv = new_argv;
+                       *argcp += count - 1;
 
-               page = malloc(page_len + 1);
-               strcpy(page, "git-");
-               strcpy(page + 4, git_cmd);
-               page[page_len] = 0;
+                       ret = 1;
+               }
        }
 
-       execlp("man", "man", page, NULL);
-}
+       if (subdir)
+               chdir(subdir);
 
-static int cmd_version(int argc, char **argv, char **envp)
-{
-       printf("git version %s\n", GIT_VERSION);
-       return 0;
-}
-
-static int cmd_help(int argc, char **argv, char **envp)
-{
-       char *help_cmd = argv[1];
-       if (!help_cmd)
-               cmd_usage(git_exec_path(), NULL);
-       show_man_page(help_cmd);
-       return 0;
+       return ret;
 }
 
-#define ARRAY_SIZE(x) (sizeof(x)/sizeof(x[0]))
+const char git_version_string[] = GIT_VERSION;
 
-static void handle_internal_command(int argc, char **argv, char **envp)
+static void handle_internal_command(int argc, const char **argv, char **envp)
 {
        const char *cmd = argv[0];
        static struct cmd_struct {
                const char *cmd;
-               int (*fn)(int, char **, char **);
+               int (*fn)(int, const char **, char **);
        } commands[] = {
                { "version", cmd_version },
                { "help", cmd_help },
+               { "log", cmd_log },
+               { "whatchanged", cmd_whatchanged },
+               { "show", cmd_show },
+               { "push", cmd_push },
+               { "format-patch", cmd_format_patch },
+               { "count-objects", cmd_count_objects },
+               { "diff", cmd_diff },
+               { "grep", cmd_grep },
+               { "rm", cmd_rm },
+               { "add", cmd_add },
+               { "rev-list", cmd_rev_list },
+               { "init-db", cmd_init_db },
+               { "get-tar-commit-id", cmd_get_tar_commit_id },
+               { "upload-tar", cmd_upload_tar },
+               { "check-ref-format", cmd_check_ref_format },
+               { "ls-files", cmd_ls_files },
+               { "ls-tree", cmd_ls_tree },
+               { "tar-tree", cmd_tar_tree },
+               { "read-tree", cmd_read_tree },
+               { "commit-tree", cmd_commit_tree },
+               { "apply", cmd_apply },
+               { "show-branch", cmd_show_branch },
+               { "diff-files", cmd_diff_files },
+               { "diff-index", cmd_diff_index },
+               { "diff-stages", cmd_diff_stages },
+               { "diff-tree", cmd_diff_tree },
+               { "cat-file", cmd_cat_file },
+               { "rev-parse", cmd_rev_parse }
        };
        int i;
 
+       /* Turn "git cmd --help" into "git help cmd" */
+       if (argc > 1 && !strcmp(argv[1], "--help")) {
+               argv[1] = argv[0];
+               argv[0] = cmd = "help";
+       }
+
        for (i = 0; i < ARRAY_SIZE(commands); i++) {
                struct cmd_struct *p = commands+i;
                if (strcmp(p->cmd, cmd))
@@ -267,12 +196,13 @@ static void handle_internal_command(int argc, char **argv, char **envp)
        }
 }
 
-int main(int argc, char **argv, char **envp)
+int main(int argc, const char **argv, char **envp)
 {
-       char *cmd = argv[0];
+       const char *cmd = argv[0];
        char *slash = strrchr(cmd, '/');
        char git_command[PATH_MAX + 1];
        const char *exec_path = NULL;
+       int done_alias = 0;
 
        /*
         * Take the basename of argv[0] as the command
@@ -341,7 +271,7 @@ int main(int argc, char **argv, char **envp)
                        puts(git_exec_path());
                        exit(0);
                }
-               cmd_usage(NULL, NULL);
+               cmd_usage(0, NULL, NULL);
        }
        argv[0] = cmd;
 
@@ -357,14 +287,24 @@ int main(int argc, char **argv, char **envp)
        exec_path = git_exec_path();
        prepend_to_path(exec_path, strlen(exec_path));
 
-       /* See if it's an internal command */
-       handle_internal_command(argc, argv, envp);
+       while (1) {
+               /* See if it's an internal command */
+               handle_internal_command(argc, argv, envp);
 
-       /* .. then try the external ones */
-       execv_git_cmd(argv);
+               /* .. then try the external ones */
+               execv_git_cmd(argv);
+
+               /* It could be an alias -- this works around the insanity
+                * of overriding "git log" with "git show" by having
+                * alias.log = show
+                */
+               if (done_alias || !handle_alias(&argc, &argv))
+                       break;
+               done_alias = 1;
+       }
 
        if (errno == ENOENT)
-               cmd_usage(exec_path, "'%s' is not a git-command", cmd);
+               cmd_usage(0, exec_path, "'%s' is not a git-command", cmd);
 
        fprintf(stderr, "Failed to run command '%s': %s\n",
                git_command, strerror(errno));