prompt.con commit tree-diff: avoid alloca for large allocations (b8ba412)
   1#include "cache.h"
   2#include "run-command.h"
   3#include "strbuf.h"
   4#include "prompt.h"
   5#include "compat/terminal.h"
   6
   7static char *do_askpass(const char *cmd, const char *prompt)
   8{
   9        struct child_process pass = CHILD_PROCESS_INIT;
  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        pass.argv = args;
  19        pass.out = -1;
  20
  21        if (start_command(&pass))
  22                return NULL;
  23
  24        strbuf_reset(&buffer);
  25        if (strbuf_read(&buffer, pass.out, 20) < 0)
  26                err = 1;
  27
  28        close(pass.out);
  29
  30        if (finish_command(&pass))
  31                err = 1;
  32
  33        if (err) {
  34                error("unable to read askpass response from '%s'", cmd);
  35                strbuf_release(&buffer);
  36                return NULL;
  37        }
  38
  39        strbuf_setlen(&buffer, strcspn(buffer.buf, "\r\n"));
  40
  41        return buffer.buf;
  42}
  43
  44char *git_prompt(const char *prompt, int flags)
  45{
  46        char *r = NULL;
  47
  48        if (flags & PROMPT_ASKPASS) {
  49                const char *askpass;
  50
  51                askpass = getenv("GIT_ASKPASS");
  52                if (!askpass)
  53                        askpass = askpass_program;
  54                if (!askpass)
  55                        askpass = getenv("SSH_ASKPASS");
  56                if (askpass && *askpass)
  57                        r = do_askpass(askpass, prompt);
  58        }
  59
  60        if (!r) {
  61                const char *err;
  62
  63                if (git_env_bool("GIT_TERMINAL_PROMPT", 1)) {
  64                        r = git_terminal_prompt(prompt, flags & PROMPT_ECHO);
  65                        err = strerror(errno);
  66                } else {
  67                        err = "terminal prompts disabled";
  68                }
  69                if (!r) {
  70                        /* prompts already contain ": " at the end */
  71                        die("could not read %s%s", prompt, err);
  72                }
  73        }
  74        return r;
  75}