strbuf_read(): skip unnecessary strbuf_grow() at eof
[git] / prompt.c
1 #include "cache.h"
2 #include "run-command.h"
3 #include "strbuf.h"
4 #include "prompt.h"
5 #include "compat/terminal.h"
6
7 static char *do_askpass(const char *cmd, const char *prompt)
8 {
9         struct child_process pass;
10         const char *args[3];
11         static struct strbuf buffer = STRBUF_INIT;
12         int err = 0;
13
14         args[0] = cmd;
15         args[1] = prompt;
16         args[2] = NULL;
17
18         memset(&pass, 0, sizeof(pass));
19         pass.argv = args;
20         pass.out = -1;
21
22         if (start_command(&pass))
23                 return NULL;
24
25         strbuf_reset(&buffer);
26         if (strbuf_read(&buffer, pass.out, 20) < 0)
27                 err = 1;
28
29         close(pass.out);
30
31         if (finish_command(&pass))
32                 err = 1;
33
34         if (err) {
35                 error("unable to read askpass response from '%s'", cmd);
36                 strbuf_release(&buffer);
37                 return NULL;
38         }
39
40         strbuf_setlen(&buffer, strcspn(buffer.buf, "\r\n"));
41
42         return buffer.buf;
43 }
44
45 char *git_prompt(const char *prompt, int flags)
46 {
47         char *r = NULL;
48
49         if (flags & PROMPT_ASKPASS) {
50                 const char *askpass;
51
52                 askpass = getenv("GIT_ASKPASS");
53                 if (!askpass)
54                         askpass = askpass_program;
55                 if (!askpass)
56                         askpass = getenv("SSH_ASKPASS");
57                 if (askpass && *askpass)
58                         r = do_askpass(askpass, prompt);
59         }
60
61         if (!r)
62                 r = git_terminal_prompt(prompt, flags & PROMPT_ECHO);
63         if (!r) {
64                 /* prompts already contain ": " at the end */
65                 die("could not read %s%s", prompt, strerror(errno));
66         }
67         return r;
68 }
69
70 char *git_getpass(const char *prompt)
71 {
72         return git_prompt(prompt, PROMPT_ASKPASS);
73 }