Use png.h and config.mk

5 files changed, 148 insertions, 70 deletions

diff --git a/.gitignore b/.gitignore
index f9ac67d..714260a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,6 +1,7 @@
 *.o
 chroot.tar
 client
+config.mk
 image
 merge
 meta
diff --git a/Darwin.mk b/Darwin.mk
new file mode 100644
index 0000000..6a2f53f
--- /dev/null
+++ b/Darwin.mk
@@ -0,0 +1,2 @@
+LDFLAGS =
+LDLIBS = -lcurses
diff --git a/Makefile b/Makefile
index ec80687..91ab927 100644
--- a/Makefile
+++ b/Makefile
@@ -1,55 +1,57 @@
 CHROOT_USER = torus
 CHROOT_GROUP = $(CHROOT_USER)
 
-CFLAGS += -Wall -Wextra -Wpedantic
-LDFLAGS += -static
-LDLIBS = -lcursesw -lutil -lz
-BINS = server client image meta merge
+CFLAGS += -std=c11 -Wall -Wextra -Wpedantic
+LDFLAGS = -static
+LDLIBS = -lcursesw -lutil
+
+-include config.mk
+
+BINS = client image merge meta server
 OBJS = $(BINS:%=%.o)
 
 all: tags $(BINS)
 
-.o:
-	$(CC) $(LDFLAGS) $< $(LDLIBS) -o $@
-
 $(OBJS): torus.h
 
 client.o: help.h
 
-help.h:
-	head -c 4096 torus.dat \
-		| file2c -s -x 'static const uint8_t HelpData[] = {' '};' \
-		> help.h
-	echo 'static const struct Tile *Help = (const struct Tile *)HelpData;' \
-		>> help.h
+image.o: png.h
+
+.o:
+	$(CC) $(LDFLAGS) $< $(LDLIBS) -o $@
 
 tags: *.h *.c
 	ctags -w *.h *.c
 
-chroot.tar: server client
-	mkdir -p root
+chroot.tar: client server
 	install -d -o root -g wheel \
+		root \
 		root/bin \
 		root/home \
-		root/usr \
-		root/usr/share \
 		root/usr/share/misc \
-		root/var \
 		root/var/run
 	install -d -o $(CHROOT_USER) -g $(CHROOT_GROUP) root/home/$(CHROOT_USER)
 	install -d -o $(CHROOT_USER) -g $(CHROOT_GROUP) root/var/run/torus
-	cp -a -f /usr/share/locale root/usr/share
-	cp -p -f /usr/share/misc/termcap.db root/usr/share/misc
-	cp -p -f /rescue/sh root/bin
-	install -o root -g wheel -m 555 server client root/bin
-	tar -c -f chroot.tar -C root bin home usr var
+	cp -af /usr/share/locale root/usr/share
+	cp -fp /usr/share/misc/termcap.db root/usr/share/misc
+	cp -fp /rescue/sh root/bin
+	install client server root/bin
+	tar -cf chroot.tar -C root bin home usr var
+
+install: chroot.tar rc.torus
+	tar -xf chroot.tar -C /home/$(CHROOT_USER)
+	install rc.torus /usr/local/etc/rc.d/torus
 
 clean:
-	rm -f tags $(OBJS) $(BINS) chroot.tar
+	rm -f $(OBJS) $(BINS) tags root chroot.tar
 
-README: torus.1
-	mandoc torus.1 | col -b -x > README
+help.h:
+	head -c 4096 torus.dat \
+		| file2c -sx 'static const uint8_t HelpData[] = {' '};' \
+		> help.h
+	echo 'static const struct Tile *Help = (const struct Tile *)HelpData;' \
+		>> help.h
 
-install: chroot.tar rc.torus
-	tar -x -f chroot.tar -C /home/$(CHROOT_USER)
-	install rc.torus /usr/local/etc/rc.d/torus
+README: torus.1
+	mandoc torus.1 | col -bx > README
diff --git a/image.c b/image.c
index e363afb..57e3a38 100644
--- a/image.c
+++ b/image.c
@@ -14,7 +14,6 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <arpa/inet.h>
 #include <err.h>
 #include <fcntl.h>
 #include <stdint.h>
@@ -25,8 +24,8 @@
 #include <sys/stat.h>
 #include <sysexits.h>
 #include <unistd.h>
-#include <zlib.h>
 
+#include "png.h"
 #include "torus.h"
 
 static const uint8_t Palette[16][3] = {
@@ -106,40 +105,15 @@ static void tilesMap(const char *path) {
 	if (error) err(EX_OSERR, "madvise");
 }
 
-static uint32_t crc;
-static void pngWrite(const void *ptr, size_t size) {
-	fwrite(ptr, size, 1, stdout);
-	if (ferror(stdout)) err(EX_IOERR, "(stdout)");
-	crc = crc32(crc, ptr, size);
-}
-static void pngInt(uint32_t host) {
-	uint32_t net = htonl(host);
-	pngWrite(&net, 4);
-}
-static void pngChunk(char type[static 4], uint32_t size) {
-	pngInt(size);
-	crc = crc32(0, Z_NULL, 0);
-	pngWrite(type, 4);
-}
-
 static void render(uint32_t tileX, uint32_t tileY) {
 	uint32_t width = CellCols * font.glyph.width;
 	uint32_t height = CellRows * font.glyph.height;
 
-	pngWrite("\x89PNG\r\n\x1A\n", 8);
-
-	pngChunk("IHDR", 13);
-	pngInt(width);
-	pngInt(height);
-	pngWrite("\x08\x03\x00\x00\x00", 5);
-	pngInt(crc);
-
-	pngChunk("PLTE", sizeof(Palette));
-	pngWrite(Palette, sizeof(Palette));
-	pngInt(crc);
+	pngHead(stdout, width, height, 8, PNGIndexed);
+	pngPalette(stdout, (uint8_t *)Palette, sizeof(Palette));
 
 	uint8_t data[height][1 + width];
-	memset(data, 0, sizeof(data));
+	memset(data, PNGNone, sizeof(data));
 
 	uint32_t widthBytes = (font.glyph.width + 7) / 8;
 	uint8_t (*bits)[font.glyph.len][font.glyph.height][widthBytes];
@@ -163,17 +137,8 @@ static void render(uint32_t tileX, uint32_t tileY) {
 		}
 	}
 
-	uLong size = compressBound(sizeof(data));
-	uint8_t deflate[size];
-	int error = compress(deflate, &size, (Byte *)data, sizeof(data));
-	if (error != Z_OK) errx(EX_SOFTWARE, "compress: %d", error);
-
-	pngChunk("IDAT", size);
-	pngWrite(deflate, size);
-	pngInt(crc);
-
-	pngChunk("IEND", 0);
-	pngInt(crc);
+	pngData(stdout, (uint8_t *)data, sizeof(data));
+	pngTail(stdout);
 }
 
 int main(int argc, char *argv[]) {
diff --git a/png.h b/png.h
new file mode 100644
index 0000000..4eb4da1
--- /dev/null
+++ b/png.h
@@ -0,0 +1,108 @@
+/* Copyright (C) 2018  Curtis McEnroe <june@causal.agency>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <err.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sysexits.h>
+
+static inline uint32_t pngCRCTable(uint8_t n) {
+	static uint32_t table[256];
+	if (table[1]) return table[n];
+	for (int i = 0; i < 256; ++i) {
+		table[i] = i;
+		for (int j = 0; j < 8; ++j) {
+			table[i] = (table[i] >> 1) ^ (table[i] & 1 ? 0xEDB88320 : 0);
+		}
+	}
+	return table[n];
+}
+
+static uint32_t pngCRC;
+
+static inline void pngWrite(FILE *file, const uint8_t *ptr, uint32_t len) {
+	if (!fwrite(ptr, len, 1, file)) err(EX_IOERR, "pngWrite");
+	for (uint32_t i = 0; i < len; ++i) {
+		pngCRC = pngCRCTable(pngCRC ^ ptr[i]) ^ (pngCRC >> 8);
+	}
+}
+static inline void pngInt32(FILE *file, uint32_t n) {
+	pngWrite(file, (uint8_t []) { n >> 24, n >> 16, n >> 8, n }, 4);
+}
+static inline void pngChunk(FILE *file, char type[static 4], uint32_t len) {
+	pngInt32(file, len);
+	pngCRC = ~0;
+	pngWrite(file, (uint8_t *)type, 4);
+}
+
+enum {
+	PNGGrayscale,
+	PNGTruecolor = 2,
+	PNGIndexed,
+	PNGAlpha,
+};
+
+static inline void pngHead(
+	FILE *file, uint32_t width, uint32_t height, uint8_t depth, uint8_t color
+) {
+	pngWrite(file, (uint8_t *)"\x89PNG\r\n\x1A\n", 8);
+	pngChunk(file, "IHDR", 13);
+	pngInt32(file, width);
+	pngInt32(file, height);
+	pngWrite(file, &depth, 1);
+	pngWrite(file, &color, 1);
+	pngWrite(file, (uint8_t []) { 0, 0, 0 }, 3);
+	pngInt32(file, ~pngCRC);
+}
+
+static inline void pngPalette(FILE *file, const uint8_t *pal, uint32_t len) {
+	pngChunk(file, "PLTE", len);
+	pngWrite(file, pal, len);
+	pngInt32(file, ~pngCRC);
+}
+
+enum {
+	PNGNone,
+	PNGSub,
+	PNGUp,
+	PNGAverage,
+	PNGPaeth,
+};
+
+static inline void pngData(FILE *file, const uint8_t *data, uint32_t len) {
+	uint32_t adler1 = 1, adler2 = 0;
+	for (uint32_t i = 0; i < len; ++i) {
+		adler1 = (adler1 + data[i]) % 65521;
+		adler2 = (adler1 + adler2) % 65521;
+	}
+	uint32_t zlen = 2 + 5 * ((len + 0xFFFE) / 0xFFFF) + len + 4;
+	pngChunk(file, "IDAT", zlen);
+	pngWrite(file, (uint8_t []) { 0x08, 0x1D }, 2);
+	for (; len > 0xFFFF; data += 0xFFFF, len -= 0xFFFF) {
+		pngWrite(file, (uint8_t []) { 0x00, 0xFF, 0xFF, 0x00, 0x00 }, 5);
+		pngWrite(file, data, 0xFFFF);
+	}
+	pngWrite(file, (uint8_t []) { 0x01, len, len >> 8, ~len, ~len >> 8 }, 5);
+	pngWrite(file, data, len);
+	pngInt32(file, adler2 << 16 | adler1);
+	pngInt32(file, ~pngCRC);
+}
+
+static inline void pngTail(FILE *file) {
+	pngChunk(file, "IEND", 0);
+	pngInt32(file, ~pngCRC);
+}