Merge branch 'cp/git-flush-is-an-env-bool'
[alt-git.git] / shell.c
blob2ece8b16e2e8e1e3473dbc7bae6deedea51ee4e8
1 #include "git-compat-util.h"
2 #include "quote.h"
3 #include "exec-cmd.h"
4 #include "strbuf.h"
5 #include "run-command.h"
6 #include "alias.h"
8 #define COMMAND_DIR "git-shell-commands"
9 #define HELP_COMMAND COMMAND_DIR "/help"
10 #define NOLOGIN_COMMAND COMMAND_DIR "/no-interactive-login"
12 static int do_generic_cmd(const char *me, char *arg)
14 const char *my_argv[4];
16 setup_path();
17 if (!arg || !(arg = sq_dequote(arg)) || *arg == '-')
18 die("bad argument");
19 if (!skip_prefix(me, "git-", &me))
20 die("bad command");
22 my_argv[0] = me;
23 my_argv[1] = arg;
24 my_argv[2] = NULL;
26 return execv_git_cmd(my_argv);
29 static int is_valid_cmd_name(const char *cmd)
31 /* Test command contains no . or / characters */
32 return cmd[strcspn(cmd, "./")] == '\0';
35 static char *make_cmd(const char *prog)
37 return xstrfmt("%s/%s", COMMAND_DIR, prog);
40 static void cd_to_homedir(void)
42 const char *home = getenv("HOME");
43 if (!home)
44 die("could not determine user's home directory; HOME is unset");
45 if (chdir(home) == -1)
46 die("could not chdir to user's home directory");
49 #define MAX_INTERACTIVE_COMMAND (4*1024*1024)
51 static void run_shell(void)
53 int done = 0;
54 struct child_process help_cmd = CHILD_PROCESS_INIT;
56 if (!access(NOLOGIN_COMMAND, F_OK)) {
57 /* Interactive login disabled. */
58 struct child_process nologin_cmd = CHILD_PROCESS_INIT;
59 int status;
61 strvec_push(&nologin_cmd.args, NOLOGIN_COMMAND);
62 status = run_command(&nologin_cmd);
63 if (status < 0)
64 exit(127);
65 exit(status);
68 /* Print help if enabled */
69 help_cmd.silent_exec_failure = 1;
70 strvec_push(&help_cmd.args, HELP_COMMAND);
71 run_command(&help_cmd);
73 do {
74 const char *prog;
75 char *full_cmd;
76 char *rawargs;
77 size_t len;
78 char *split_args;
79 const char **argv;
80 int code;
81 int count;
83 fprintf(stderr, "git> ");
86 * Avoid using a strbuf or git_read_line_interactively() here.
87 * We don't want to allocate arbitrary amounts of memory on
88 * behalf of a possibly untrusted client, and we're subject to
89 * OS limits on command length anyway.
91 fflush(stdout);
92 rawargs = xmalloc(MAX_INTERACTIVE_COMMAND);
93 if (!fgets(rawargs, MAX_INTERACTIVE_COMMAND, stdin)) {
94 fprintf(stderr, "\n");
95 free(rawargs);
96 break;
98 len = strlen(rawargs);
101 * If we truncated due to our input buffer size, reject the
102 * command. That's better than running bogus input, and
103 * there's a good chance it's just malicious garbage anyway.
105 if (len >= MAX_INTERACTIVE_COMMAND - 1)
106 die("invalid command format: input too long");
108 if (len > 0 && rawargs[len - 1] == '\n') {
109 if (--len > 0 && rawargs[len - 1] == '\r')
110 --len;
111 rawargs[len] = '\0';
114 split_args = xstrdup(rawargs);
115 count = split_cmdline(split_args, &argv);
116 if (count < 0) {
117 fprintf(stderr, "invalid command format '%s': %s\n", rawargs,
118 split_cmdline_strerror(count));
119 free(split_args);
120 free(rawargs);
121 continue;
124 prog = argv[0];
125 if (!strcmp(prog, "")) {
126 } else if (!strcmp(prog, "quit") || !strcmp(prog, "logout") ||
127 !strcmp(prog, "exit") || !strcmp(prog, "bye")) {
128 done = 1;
129 } else if (is_valid_cmd_name(prog)) {
130 struct child_process cmd = CHILD_PROCESS_INIT;
132 full_cmd = make_cmd(prog);
133 argv[0] = full_cmd;
134 cmd.silent_exec_failure = 1;
135 strvec_pushv(&cmd.args, argv);
136 code = run_command(&cmd);
137 if (code == -1 && errno == ENOENT) {
138 fprintf(stderr, "unrecognized command '%s'\n", prog);
140 free(full_cmd);
141 } else {
142 fprintf(stderr, "invalid command format '%s'\n", prog);
145 free(argv);
146 free(rawargs);
147 } while (!done);
150 static struct commands {
151 const char *name;
152 int (*exec)(const char *me, char *arg);
153 } cmd_list[] = {
154 { "git-receive-pack", do_generic_cmd },
155 { "git-upload-pack", do_generic_cmd },
156 { "git-upload-archive", do_generic_cmd },
157 { NULL },
160 int cmd_main(int argc, const char **argv)
162 char *prog;
163 const char **user_argv;
164 struct commands *cmd;
165 int count;
168 * Special hack to pretend to be a CVS server
170 if (argc == 2 && !strcmp(argv[1], "cvs server")) {
171 argv--;
172 } else if (argc == 1) {
173 /* Allow the user to run an interactive shell */
174 cd_to_homedir();
175 if (access(COMMAND_DIR, R_OK | X_OK) == -1) {
176 die("Interactive git shell is not enabled.\n"
177 "hint: ~/" COMMAND_DIR " should exist "
178 "and have read and execute access.");
180 run_shell();
181 exit(0);
182 } else if (argc != 3 || strcmp(argv[1], "-c")) {
184 * We do not accept any other modes except "-c" followed by
185 * "cmd arg", where "cmd" is a very limited subset of git
186 * commands or a command in the COMMAND_DIR
188 die("Run with no arguments or with -c cmd");
191 prog = xstrdup(argv[2]);
192 if (!strncmp(prog, "git", 3) && isspace(prog[3]))
193 /* Accept "git foo" as if the caller said "git-foo". */
194 prog[3] = '-';
196 for (cmd = cmd_list ; cmd->name ; cmd++) {
197 int len = strlen(cmd->name);
198 char *arg;
199 if (strncmp(cmd->name, prog, len))
200 continue;
201 arg = NULL;
202 switch (prog[len]) {
203 case '\0':
204 arg = NULL;
205 break;
206 case ' ':
207 arg = prog + len + 1;
208 break;
209 default:
210 continue;
212 return cmd->exec(cmd->name, arg);
215 cd_to_homedir();
216 count = split_cmdline(prog, &user_argv);
217 if (count >= 0) {
218 if (is_valid_cmd_name(user_argv[0])) {
219 prog = make_cmd(user_argv[0]);
220 user_argv[0] = prog;
221 execv(user_argv[0], (char *const *) user_argv);
223 free(prog);
224 free(user_argv);
225 die("unrecognized command '%s'", argv[2]);
226 } else {
227 free(prog);
228 die("invalid command format '%s': %s", argv[2],
229 split_cmdline_strerror(count));