Merge branch 'jk/ident-loosen-getpwuid' into maint

When getpwuid() on the system returned NULL (e.g. the user is not
in the /etc/passwd file or other uid-to-name mappings), the
codepath to find who the user is to record it in the reflog barfed
and died.  Loosen the check in this codepath, which already accepts
questionable ident string (e.g. host part of the e-mail address is
obviously bogus), and in general when we operate fmt_ident() function
in non-strict mode.

* jk/ident-loosen-getpwuid:
  ident: loosen getpwuid error in non-strict mode
  ident: keep a flag for bogus default_email
  ident: make xgetpwuid_self() a static local helper

git-compat-util.h

@@ -923,9 +923,6 @@ int access_or_die(const char *path, int mode, unsigned flag);
 /* Warn on an inaccessible file that ought to be accessible */
 void warn_on_inaccessible(const char *path);
 
-/* Get the passwd entry for the UID of the current process. */
-struct passwd *xgetpwuid_self(void);
-
 #ifdef GMTIME_UNRELIABLE_ERRORS
 struct tm *git_gmtime(const time_t *);
 struct tm *git_gmtime_r(const time_t *, struct tm *);

ident.c

@@ -10,6 +10,8 @@
 static struct strbuf git_default_name = STRBUF_INIT;
 static struct strbuf git_default_email = STRBUF_INIT;
 static struct strbuf git_default_date = STRBUF_INIT;
+static int default_email_is_bogus;
+static int default_name_is_bogus;
 
 #define IDENT_NAME_GIVEN 01
 #define IDENT_MAIL_GIVEN 02
@@ -23,6 +25,25 @@ static int author_ident_explicitly_given;
 #define get_gecos(struct_passwd) ((struct_passwd)->pw_gecos)
 #endif
 
+static struct passwd *xgetpwuid_self(int *is_bogus)
+{
+	struct passwd *pw;
+
+	errno = 0;
+	pw = getpwuid(getuid());
+	if (!pw) {
+		static struct passwd fallback;
+		fallback.pw_name = "unknown";
+#ifndef NO_GECOS_IN_PWENT
+		fallback.pw_gecos = "Unknown";
+#endif
+		pw = &fallback;
+		if (is_bogus)
+			*is_bogus = 1;
+	}
+	return pw;
+}
+
 static void copy_gecos(const struct passwd *w, struct strbuf *name)
 {
 	char *src;
@@ -96,22 +117,26 @@ static int canonical_name(const char *host, struct strbuf *out)
 	return status;
 }
 
-static void add_domainname(struct strbuf *out)
+static void add_domainname(struct strbuf *out, int *is_bogus)
 {
 	char buf[1024];
 
 	if (gethostname(buf, sizeof(buf))) {
 		warning("cannot get host name: %s", strerror(errno));
 		strbuf_addstr(out, "(none)");
+		*is_bogus = 1;
 		return;
 	}
 	if (strchr(buf, '.'))
 		strbuf_addstr(out, buf);
-	else if (canonical_name(buf, out) < 0)
+	else if (canonical_name(buf, out) < 0) {
 		strbuf_addf(out, "%s.(none)", buf);
+		*is_bogus = 1;
+	}
 }
 
-static void copy_email(const struct passwd *pw, struct strbuf *email)
+static void copy_email(const struct passwd *pw, struct strbuf *email,
+		       int *is_bogus)
 {
 	/*
 	 * Make up a fake email address
@@ -122,13 +147,13 @@ static void copy_email(const struct passwd *pw, struct strbuf *email)
 
 	if (!add_mailname_host(email))
 		return;	/* read from "/etc/mailname" (Debian) */
-	add_domainname(email);
+	add_domainname(email, is_bogus);
 }
 
 const char *ident_default_name(void)
 {
 	if (!git_default_name.len) {
-		copy_gecos(xgetpwuid_self(), &git_default_name);
+		copy_gecos(xgetpwuid_self(&default_name_is_bogus), &git_default_name);
 		strbuf_trim(&git_default_name);
 	}
 	return git_default_name.buf;
@@ -144,7 +169,8 @@ const char *ident_default_email(void)
 			committer_ident_explicitly_given |= IDENT_MAIL_GIVEN;
 			author_ident_explicitly_given |= IDENT_MAIL_GIVEN;
 		} else
-			copy_email(xgetpwuid_self(), &git_default_email);
+			copy_email(xgetpwuid_self(&default_email_is_bogus),
+				   &git_default_email, &default_email_is_bogus);
 		strbuf_trim(&git_default_email);
 	}
 	return git_default_email.buf;
@@ -332,12 +358,17 @@ const char *fmt_ident(const char *name, const char *email,
 				fputs(env_hint, stderr);
 			die("empty ident name (for <%s>) not allowed", email);
 		}
-		pw = xgetpwuid_self();
+		pw = xgetpwuid_self(NULL);
 		name = pw->pw_name;
 	}
 
-	if (strict && email == git_default_email.buf &&
-	    strstr(email, "(none)")) {
+	if (want_name && strict &&
+	    name == git_default_name.buf && default_name_is_bogus) {
+		fputs(env_hint, stderr);
+		die("unable to auto-detect name (got '%s')", name);
+	}
+
+	if (strict && email == git_default_email.buf && default_email_is_bogus) {
 		fputs(env_hint, stderr);
 		die("unable to auto-detect email address (got '%s')", email);
 	}

wrapper.c

@@ -601,18 +601,6 @@ int access_or_die(const char *path, int mode, unsigned flag)
 	return ret;
 }
 
-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;
-}
-
 char *xgetcwd(void)
 {
 	struct strbuf sb = STRBUF_INIT;