Enable git status reporting.

Also reorganize git.c to contain most of the implementation details,
main just calls the functions without any arguments.

ep.c

@@ -47,7 +47,7 @@ int main(int argc, char **argv)
 
 	/* start threads for long(er) running steps */
 	pthread_t git_handle;
-	if (pthread_create(&git_handle, NULL, get_git_branch_name, NULL)) {
+	if (pthread_create(&git_handle, NULL, git_thread, NULL)) {
 		e(WARN, "couldn't create git thread", errno);
 	}
 
@@ -67,10 +67,7 @@ int main(int argc, char **argv)
 
 	/* git status */
 	pthread_join(git_handle, NULL);
-	if (git_branch_name) {
-		p(" ");
-		p(git_branch_name);
-	}
+	print_git();
 
 	/* print currently active shell jobs */
 	if (shell_jobs) {

ep.h

@@ -15,7 +15,7 @@ extern const int fish_style_dir;
 void print_pwd(const char *);
 
 /* from git.c */
-extern char *git_branch_name;
-void *get_git_branch_name(void *);
+void *git_thread(void *);
+void print_git(void);
 
 #endif

git.c

@@ -1,30 +1,88 @@
+#include <string.h>
 #include <stdio.h>
+#include <stdlib.h>
 
 #include "ep.h"
 
-char *git_branch_name;
+static char *git_branch_name, *git_status;
+void print_git(void)
+{
+	if (git_branch_name) {
+		p(" ");
+		p(git_branch_name);
 
-void *get_git_branch_name(void *arg)
+		if (git_status) {
+			p(" [");
+			p(git_status);
+			p("]");
+		}
+	}
+}
+
+struct rlfc_data {
+	char *line;
+	size_t n;
+	ssize_t l;
+	int status;
+};
+
+static void read_line_from_command(const char *c, struct rlfc_data *d)
 {
 	FILE *f = popen("git rev-parse --abbrev-ref HEAD 2>/dev/null", "re");
-	if (!f) {
+	if (!f)
+		return;
+
+	d->l = getline(&d->line, &d->n, f);
+	d->status = pclose(f);
+}
+
+static char *get_git_status(void);
+
+void *git_thread(void *arg)
+{
+	struct rlfc_data c = { 0 };
+	read_line_from_command("git rev-parse --abbrev-ref HEAD 2>/dev/null", &c);
+
+	if (!c.status) {
+		/* if git exits with 0, we are in a repo */
+
+		if (c.l > 0) {
+			/* TODO: treat case where it reads HEAD */
+			c.line[c.l-1] = 0;
+			/* line ownserhip goes to outside this function */
+			git_branch_name = c.line;
+		}
+	} else {
 		return NULL;
 	}
 
-	char *line = NULL;
-	size_t n = 0;
-	ssize_t l = getline(&line, &n, f);
+	/* since we are in a repo, read git status;
+	 * if we add more stuff to do in repos, launch more threads */
 
-	if (!pclose(f)) {
-		/* if git exits with 0, we are in a repo */
-
-		if (l > 0) {
-			/* TODO: treat case where it reads HEAD */
-			line[l-1] = 0;
-			/* line ownserhip goes to outside this function */
-			git_branch_name = line;
-		}
-	}
+	get_git_status();
 
 	return NULL;
 }
+
+static char *get_git_status(void)
+{
+	size_t modified = 0;
+
+	FILE *f = popen("git status --porcelain=v1 -z 2>/dev/null", "re");
+	if (!f)
+		return NULL;
+
+	char *line = NULL;
+	size_t n = 0;
+	ssize_t l;
+	while ((l = getdelim(&line, &n, 0, f)) != -1) {
+		modified += l>4 && line[1] == 'M';
+	}
+	free(line);
+
+	if (!pclose(f)) {
+		asprintf(&git_status, "~%zu", modified);
+	}
+
+	return git_status;
+}