git-save: improve commit authorship data

We used to always just commit as "subsurface@hohndel.org" because
libgit-19 doesn't have the interfaces to do user name lookup.  This does
better if you have libgit-20, using "git_signature_default()" to get the
actual user that does the saving.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

1 files changed, 23 insertions, 0 deletions

diff --git a/linux.c b/linux.c
index ea0170dc8..8c79a3f2d 100644
--- a/linux.c
+++ b/linux.c
@@ -2,16 +2,39 @@
 /* implements Linux specific functions */
 #include "dive.h"
 #include "display.h"
+#include "membuffer.h"
 #include <string.h>
 #include <sys/types.h>
 #include <dirent.h>
 #include <fnmatch.h>
 #include <stdio.h>
 #include <fcntl.h>
+#include <unistd.h>
+#include <pwd.h>
 
 const char system_divelist_default_font[] = "Sans";
 const int system_divelist_default_font_size = 8;
 
+void subsurface_user_info(struct user_info *user)
+{
+	struct passwd *pwd = getpwuid(getuid());
+	const char *username = getenv("USER");
+
+	if (pwd) {
+		if (pwd->pw_gecos && *pwd->pw_gecos)
+			user->name = pwd->pw_gecos;
+		if (!username)
+			username = pwd->pw_name;
+	}
+	if (username && *username) {
+		char hostname[64];
+		struct membuffer mb = { 0 };
+		gethostname(hostname, sizeof(hostname));
+		put_format(&mb, "%s@%s", username, hostname);
+		user->email = mb_cstring(&mb);
+	}
+}
+
 const char *system_default_filename(void)
 {
 	const char *home, *user;