git/credential.c
Jeff King cf4fff579e refactor skip_prefix to return a boolean
The skip_prefix() function returns a pointer to the content
past the prefix, or NULL if the prefix was not found. While
this is nice and simple, in practice it makes it hard to use
for two reasons:

  1. When you want to conditionally skip or keep the string
     as-is, you have to introduce a temporary variable.
     For example:

       tmp = skip_prefix(buf, "foo");
       if (tmp)
	       buf = tmp;

  2. It is verbose to check the outcome in a conditional, as
     you need extra parentheses to silence compiler
     warnings. For example:

       if ((cp = skip_prefix(buf, "foo"))
	       /* do something with cp */

Both of these make it harder to use for long if-chains, and
we tend to use starts_with() instead. However, the first line
of "do something" is often to then skip forward in buf past
the prefix, either using a magic constant or with an extra
strlen(3) (which is generally computed at compile time, but
means we are repeating ourselves).

This patch refactors skip_prefix() to return a simple boolean,
and to provide the pointer value as an out-parameter. If the
prefix is not found, the out-parameter is untouched. This
lets you write:

  if (skip_prefix(arg, "foo ", &arg))
	  do_foo(arg);
  else if (skip_prefix(arg, "bar ", &arg))
	  do_bar(arg);

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-20 10:44:43 -07:00

367 lines
7.6 KiB
C

#include "cache.h"
#include "credential.h"
#include "string-list.h"
#include "run-command.h"
#include "url.h"
#include "prompt.h"
void credential_init(struct credential *c)
{
memset(c, 0, sizeof(*c));
c->helpers.strdup_strings = 1;
}
void credential_clear(struct credential *c)
{
free(c->protocol);
free(c->host);
free(c->path);
free(c->username);
free(c->password);
string_list_clear(&c->helpers, 0);
credential_init(c);
}
int credential_match(const struct credential *want,
const struct credential *have)
{
#define CHECK(x) (!want->x || (have->x && !strcmp(want->x, have->x)))
return CHECK(protocol) &&
CHECK(host) &&
CHECK(path) &&
CHECK(username);
#undef CHECK
}
static int credential_config_callback(const char *var, const char *value,
void *data)
{
struct credential *c = data;
const char *key, *dot;
if (!skip_prefix(var, "credential.", &key))
return 0;
if (!value)
return config_error_nonbool(var);
dot = strrchr(key, '.');
if (dot) {
struct credential want = CREDENTIAL_INIT;
char *url = xmemdupz(key, dot - key);
int matched;
credential_from_url(&want, url);
matched = credential_match(&want, c);
credential_clear(&want);
free(url);
if (!matched)
return 0;
key = dot + 1;
}
if (!strcmp(key, "helper"))
string_list_append(&c->helpers, value);
else if (!strcmp(key, "username")) {
if (!c->username)
c->username = xstrdup(value);
}
else if (!strcmp(key, "usehttppath"))
c->use_http_path = git_config_bool(var, value);
return 0;
}
static int proto_is_http(const char *s)
{
if (!s)
return 0;
return !strcmp(s, "https") || !strcmp(s, "http");
}
static void credential_apply_config(struct credential *c)
{
if (c->configured)
return;
git_config(credential_config_callback, c);
c->configured = 1;
if (!c->use_http_path && proto_is_http(c->protocol)) {
free(c->path);
c->path = NULL;
}
}
static void credential_describe(struct credential *c, struct strbuf *out)
{
if (!c->protocol)
return;
strbuf_addf(out, "%s://", c->protocol);
if (c->username && *c->username)
strbuf_addf(out, "%s@", c->username);
if (c->host)
strbuf_addstr(out, c->host);
if (c->path)
strbuf_addf(out, "/%s", c->path);
}
static char *credential_ask_one(const char *what, struct credential *c,
int flags)
{
struct strbuf desc = STRBUF_INIT;
struct strbuf prompt = STRBUF_INIT;
char *r;
credential_describe(c, &desc);
if (desc.len)
strbuf_addf(&prompt, "%s for '%s': ", what, desc.buf);
else
strbuf_addf(&prompt, "%s: ", what);
r = git_prompt(prompt.buf, flags);
strbuf_release(&desc);
strbuf_release(&prompt);
return xstrdup(r);
}
static void credential_getpass(struct credential *c)
{
if (!c->username)
c->username = credential_ask_one("Username", c,
PROMPT_ASKPASS|PROMPT_ECHO);
if (!c->password)
c->password = credential_ask_one("Password", c,
PROMPT_ASKPASS);
}
int credential_read(struct credential *c, FILE *fp)
{
struct strbuf line = STRBUF_INIT;
while (strbuf_getline(&line, fp, '\n') != EOF) {
char *key = line.buf;
char *value = strchr(key, '=');
if (!line.len)
break;
if (!value) {
warning("invalid credential line: %s", key);
strbuf_release(&line);
return -1;
}
*value++ = '\0';
if (!strcmp(key, "username")) {
free(c->username);
c->username = xstrdup(value);
} else if (!strcmp(key, "password")) {
free(c->password);
c->password = xstrdup(value);
} else if (!strcmp(key, "protocol")) {
free(c->protocol);
c->protocol = xstrdup(value);
} else if (!strcmp(key, "host")) {
free(c->host);
c->host = xstrdup(value);
} else if (!strcmp(key, "path")) {
free(c->path);
c->path = xstrdup(value);
} else if (!strcmp(key, "url")) {
credential_from_url(c, value);
}
/*
* Ignore other lines; we don't know what they mean, but
* this future-proofs us when later versions of git do
* learn new lines, and the helpers are updated to match.
*/
}
strbuf_release(&line);
return 0;
}
static void credential_write_item(FILE *fp, const char *key, const char *value)
{
if (!value)
return;
fprintf(fp, "%s=%s\n", key, value);
}
void credential_write(const struct credential *c, FILE *fp)
{
credential_write_item(fp, "protocol", c->protocol);
credential_write_item(fp, "host", c->host);
credential_write_item(fp, "path", c->path);
credential_write_item(fp, "username", c->username);
credential_write_item(fp, "password", c->password);
}
static int run_credential_helper(struct credential *c,
const char *cmd,
int want_output)
{
struct child_process helper;
const char *argv[] = { NULL, NULL };
FILE *fp;
memset(&helper, 0, sizeof(helper));
argv[0] = cmd;
helper.argv = argv;
helper.use_shell = 1;
helper.in = -1;
if (want_output)
helper.out = -1;
else
helper.no_stdout = 1;
if (start_command(&helper) < 0)
return -1;
fp = xfdopen(helper.in, "w");
credential_write(c, fp);
fclose(fp);
if (want_output) {
int r;
fp = xfdopen(helper.out, "r");
r = credential_read(c, fp);
fclose(fp);
if (r < 0) {
finish_command(&helper);
return -1;
}
}
if (finish_command(&helper))
return -1;
return 0;
}
static int credential_do(struct credential *c, const char *helper,
const char *operation)
{
struct strbuf cmd = STRBUF_INIT;
int r;
if (helper[0] == '!')
strbuf_addstr(&cmd, helper + 1);
else if (is_absolute_path(helper))
strbuf_addstr(&cmd, helper);
else
strbuf_addf(&cmd, "git credential-%s", helper);
strbuf_addf(&cmd, " %s", operation);
r = run_credential_helper(c, cmd.buf, !strcmp(operation, "get"));
strbuf_release(&cmd);
return r;
}
void credential_fill(struct credential *c)
{
int i;
if (c->username && c->password)
return;
credential_apply_config(c);
for (i = 0; i < c->helpers.nr; i++) {
credential_do(c, c->helpers.items[i].string, "get");
if (c->username && c->password)
return;
}
credential_getpass(c);
if (!c->username && !c->password)
die("unable to get password from user");
}
void credential_approve(struct credential *c)
{
int i;
if (c->approved)
return;
if (!c->username || !c->password)
return;
credential_apply_config(c);
for (i = 0; i < c->helpers.nr; i++)
credential_do(c, c->helpers.items[i].string, "store");
c->approved = 1;
}
void credential_reject(struct credential *c)
{
int i;
credential_apply_config(c);
for (i = 0; i < c->helpers.nr; i++)
credential_do(c, c->helpers.items[i].string, "erase");
free(c->username);
c->username = NULL;
free(c->password);
c->password = NULL;
c->approved = 0;
}
void credential_from_url(struct credential *c, const char *url)
{
const char *at, *colon, *cp, *slash, *host, *proto_end;
credential_clear(c);
/*
* Match one of:
* (1) proto://<host>/...
* (2) proto://<user>@<host>/...
* (3) proto://<user>:<pass>@<host>/...
*/
proto_end = strstr(url, "://");
if (!proto_end)
return;
cp = proto_end + 3;
at = strchr(cp, '@');
colon = strchr(cp, ':');
slash = strchrnul(cp, '/');
if (!at || slash <= at) {
/* Case (1) */
host = cp;
}
else if (!colon || at <= colon) {
/* Case (2) */
c->username = url_decode_mem(cp, at - cp);
host = at + 1;
} else {
/* Case (3) */
c->username = url_decode_mem(cp, colon - cp);
c->password = url_decode_mem(colon + 1, at - (colon + 1));
host = at + 1;
}
if (proto_end - url > 0)
c->protocol = xmemdupz(url, proto_end - url);
if (slash - host > 0)
c->host = url_decode_mem(host, slash - host);
/* Trim leading and trailing slashes from path */
while (*slash == '/')
slash++;
if (*slash) {
char *p;
c->path = url_decode(slash);
p = c->path + strlen(c->path) - 1;
while (p > c->path && *p == '/')
*p-- = '\0';
}
}