From bf62b511ebf4be03e07a0f2aa4d01bf0289ca8b0 Mon Sep 17 00:00:00 2001
From: Armaan Bhojwani <me@armaanb.net>
Date: Mon, 5 Apr 2021 20:13:12 -0400
Subject: [PATCH] Render .md files with cmark-gfm

---
 Makefile     |  2 +-
 README       |  3 ++-
 src/stagit.c | 70 +++++++++++++++++++++++++++++++++++-----------------
 3 files changed, 51 insertions(+), 24 deletions(-)

diff --git a/Makefile b/Makefile
index 50461fd..15dcd86 100644
--- a/Makefile
+++ b/Makefile
@@ -10,7 +10,7 @@ DOCPREFIX = ${PREFIX}/share/doc/${NAME}
 SHAREPREFIX = ${PREFIX}/share/${NAME}
 
 LIBGIT_INC = -I/usr/local/include
-LIBGIT_LIB = -L/usr/local/lib -lgit2
+LIBGIT_LIB = -L/usr/local/lib -lgit2 -lcmark-gfm
 
 # use system flags.
 STAGIT_CFLAGS = ${LIBGIT_INC} ${CFLAGS}
diff --git a/README b/README
index e836994..a411c49 100644
--- a/README
+++ b/README
@@ -32,8 +32,9 @@ Dependencies
 - C compiler (C99).
 - libc (tested with OpenBSD, FreeBSD, NetBSD, Linux: glibc and musl).
 - libgit2 (v0.22+).
+- Chroma
+- cmark-gfm
 - POSIX make (optional).
-- Python3, pip.
 
 
 Documentation
diff --git a/src/stagit.c b/src/stagit.c
index 75fca67..217021e 100644
--- a/src/stagit.c
+++ b/src/stagit.c
@@ -8,11 +8,13 @@
 #include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <stdbool.h>
 #include <string.h>
 #include <time.h>
 #include <unistd.h>
 
 #include <git2.h>
+#include <cmark-gfm.h>
 
 #include "cp.h"
 #include "compat.h"
@@ -65,6 +67,8 @@ static char *readmefiles[] = { "HEAD:README", "HEAD:README.md" };
 static char *readme;
 static long long nlogcommits = -1; /* < 0 indicates not used */
 
+bool htmlized; /* true if markdoown converted to HTML */
+
 /* cache */
 static git_oid lastoid;
 static char lastoidstr[GIT_OID_HEXSZ + 2]; /* id + newline + NUL byte */
@@ -398,37 +402,57 @@ writefooter(FILE *fp)
 	fputs("</div>\n</body>\n</html>\n", fp);
 }
 
+const char *
+get_ext(const char *filename)
+{
+	const char *dot = strrchr(filename, '.');
+	if(!dot || dot == filename) return "";
+	return dot + 1;
+}
+
 int
 call_chroma(const char *filename, FILE *fp, const char *s, size_t len)
 {
+	htmlized = false;
 	// Flush HTML-file
 	fflush(fp);
-	// Copy STDOUT
-	int stdout_copy = dup(1);
-	// Redirect STDOUT
-	dup2(fileno(fp), 1);
-
-	char cmd[] = "chroma --html --html-only --html-lines --html-lines-table --filename ";
-	strcat(cmd, filename);
-
-	FILE *child = popen(cmd, "w");
-	if (child == NULL) {
-		printf("child is null: %s", strerror(errno));
-		exit(1);
-	}
 
-	// Give code to highlight through STDIN:
+	char *html = cmark_markdown_to_html(s, len, CMARK_OPT_DEFAULT);
+	if (strcmp(get_ext(filename), "md") == 0) htmlized = true;
+
 	int lc;
-	size_t i;
-	for (i = 0; *s && i < len; s++, i++) {
-		if (*s == '\n') lc++;
-		fprintf(child, "%c", *s);
+	if (!htmlized) {
+		// Copy STDOUT
+		int stdout_copy = dup(1);
+
+		// Redirect STDOUT
+		dup2(fileno(fp), 1);
+
+		char cmd[255] = "chroma --html --html-only --html-lines --html-lines-table --filename ";
+		strncat(cmd, filename, strlen(filename) + 1);
+		FILE *child = popen(cmd, "w");
+		if (child == NULL) {
+			printf("child is null: %s", strerror(errno));
+			exit(1);
+		}
+
+		// Give code to highlight through STDIN:
+		size_t i;
+		for (i = 0; *s && i < len; s++, i++) {
+			if (*s == '\n') lc++;
+			fprintf(child, "%c", *s);
+		}
+
+		pclose(child);
+		fflush(stdout);
+
+		// Give back STDOUT.
+		dup2(stdout_copy, 1);
+
+	} else {
+		fprintf(fp, "%s", html);
 	}
 
-	pclose(child);
-	fflush(stdout);
-	// Give back STDOUT.
-	dup2(stdout_copy, 1);
 	return lc;
 }
 
@@ -804,6 +828,7 @@ writeblob(git_object *obj, const char *fpath, const char *filename, git_off_t fi
 	fputs("<p> ", fp);
 	xmlencode(fp, filename, strlen(filename));
 	fprintf(fp, " (%juB)", (uintmax_t)filesize);
+
 	fputs("</p><hr/>", fp);
 
 	if (git_blob_is_binary((git_blob *)obj)) {
@@ -813,6 +838,7 @@ writeblob(git_object *obj, const char *fpath, const char *filename, git_off_t fi
 		if (ferror(fp))
 			err(1, "fwrite");
 	}
+
 	writefooter(fp);
 	fclose(fp);
 
-- 
2.39.2