ident: report passwd errors with a more friendly message

When getpwuid fails, we give a cute but cryptic message.
While it makes sense if you know that getpwuid or identity
functions are being called, this code is triggered behind
the scenes by quite a few git commands these days (e.g.,
receive-pack on a remote server might use it for a reflog;
the current message is hard to distinguish from an
authentication error).  Let's switch to something that gives
a little more context.

While we're at it, we can factor out all of the
cut-and-pastes of the "you don't exist" message into a
wrapper function. Rather than provide xgetpwuid, let's make
it even more specific to just getting the passwd entry for
the current uid. That's the only way we use getpwuid anyway,
and it lets us make an even more specific error message.

The current message also fails to mention errno. While the
usual cause for getpwuid failing is that the user does not
exist, mentioning errno makes it easier to diagnose these
problems.  Note that POSIX specifies that errno remain
untouched if the passwd entry does not exist (but will be
set on actual errors), whereas some systems will return
ENOENT or similar for a missing entry. We handle both cases
in our wrapper.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/Documentation/git-commit-tree.txt b/Documentation/git-commit-tree.txt
index eb12b2dd91506ee3139f01c0c5dbdcea86714d96..eb8ee9999eebce4baf5008e604acfee4ccda6bd8 100644 (file)
--- a/Documentation/git-commit-tree.txt
+++ b/Documentation/git-commit-tree.txt
@@ -88,11 +88,6 @@ for one to be entered and terminated with ^D.
 
 include::date-formats.txt[]
 
-Diagnostics
------------
-You don't exist. Go away!::
-    The passwd(5) gecos field couldn't be read
-
 Discussion
 ----------
 

diff --git a/Documentation/git-var.txt b/Documentation/git-var.txt
index 3f703e377562fbedc7b652cecdd2585de84dd912..67edf586896a37818de13c959fcc23479eb9bef2 100644 (file)
--- a/Documentation/git-var.txt
+++ b/Documentation/git-var.txt
@@ -59,11 +59,6 @@ ifdef::git-default-pager[]
     The build you are using chose '{git-default-pager}' as the default.
 endif::git-default-pager[]
 
-Diagnostics
------------
-You don't exist. Go away!::
-    The passwd(5) gecos field couldn't be read
-
 SEE ALSO
 --------
 linkgit:git-commit-tree[1]

diff --git a/git-compat-util.h b/git-compat-util.h
index ed11ad8119bb22db8a5428aed5525c40fbb72217..5bd9ad7d2a23773b1410ded9f4f241ebe4d4da00 100644 (file)
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -595,4 +595,7 @@ int rmdir_or_warn(const char *path);
  */
 int remove_or_warn(unsigned int mode, const char *path);
 
+/* Get the passwd entry for the UID of the current process. */
+struct passwd *xgetpwuid_self(void);
+
 #endif

diff --git a/ident.c b/ident.c
index 73a06a11fa22d5901fd17f2fa76b66f59c96742f..5aec073b96165654dc5ea88b0a08798fe4ada0e7 100644 (file)
--- a/ident.c
+++ b/ident.c
@@ -100,12 +100,8 @@ static void copy_email(const struct passwd *pw, struct strbuf *email)
 
 const char *ident_default_name(void)
 {
-       if (!git_default_name.len) {
-               struct passwd *pw = getpwuid(getuid());
-               if (!pw)
-                       die("You don't exist. Go away!");
-               copy_gecos(pw, &git_default_name);
-       }
+       if (!git_default_name.len)
+               copy_gecos(xgetpwuid_self(), &git_default_name);
        return git_default_name.buf;
 }
 
@@ -117,12 +113,8 @@ const char *ident_default_email(void)
                if (email && email[0]) {
                        strbuf_addstr(&git_default_email, email);
                        user_ident_explicitly_given |= IDENT_MAIL_GIVEN;
-               } else {
-                       struct passwd *pw = getpwuid(getuid());
-                       if (!pw)
-                               die("You don't exist. Go away!");
-                       copy_email(pw, &git_default_email);
-               }
+               } else
+                       copy_email(xgetpwuid_self(), &git_default_email);
        }
        return git_default_email.buf;
 }
@@ -303,9 +295,7 @@ const char *fmt_ident(const char *name, const char *email,
                                fputs(env_hint, stderr);
                        die("empty ident %s <%s> not allowed", name, email);
                }
-               pw = getpwuid(getuid());
-               if (!pw)
-                       die("You don't exist. Go away!");
+               pw = xgetpwuid_self();
                name = pw->pw_name;
        }
 

diff --git a/wrapper.c b/wrapper.c
index 6ccd0595f43d0ef62bd60a5863804f9a842a4235..b5e33e49c77bdf1d19292971b63ff5221b013f33 100644 (file)
--- a/wrapper.c
+++ b/wrapper.c
@@ -402,3 +402,15 @@ int remove_or_warn(unsigned int mode, const char *file)
 {
        return S_ISGITLINK(mode) ? rmdir_or_warn(file) : unlink_or_warn(file);
 }
+
+struct passwd *xgetpwuid_self(void)
+{
+       struct passwd *pw;
+
+       errno = 0;
+       pw = getpwuid(getuid());
+       if (!pw)
+               die(_("unable to look up current user in the passwd file: %s"),
+                   errno ? strerror(errno) : _("no such user"));
+       return pw;
+}