From 4df74982b149eb0614ca6a3d7789b2eb868ca699 Mon Sep 17 00:00:00 2001
From: Ali Gholami Rudi <ali@rudi.ir>
Date: Mon, 25 Feb 2013 20:36:44 +0330
Subject: [PATCH] support ppm files

---
 Makefile |  2 +-
 fbvis.c  | 32 +++++++++++++-------------------
 ppm.c    | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 70 insertions(+), 20 deletions(-)
 create mode 100644 ppm.c

diff --git a/Makefile b/Makefile
index d32321d..474f902 100644
--- a/Makefile
+++ b/Makefile
@@ -5,7 +5,7 @@ LDFLAGS = -lm
 all: fbvis
 %.o: %.c
 	$(CC) -c $(CFLAGS) $<
-fbvis: fbvis.o draw.o stb_image.o lodepng.o
+fbvis: fbvis.o draw.o ppm.o stb_image.o lodepng.o
 	$(CC) -o $@ $^ $(LDFLAGS)
 clean:
 	rm -f *.o fbvis
diff --git a/fbvis.c b/fbvis.c
index 07083cb..5131326 100644
--- a/fbvis.c
+++ b/fbvis.c
@@ -24,8 +24,9 @@
 #define MAX(a, b)	((a) > (b) ? (a) : (b))
 #define REGION(a, b, x)	(MIN(b, MAX(x, a)))
 
-static int cols, rows, ch;
-static char *buf;
+static int cols, rows;
+static int ch;
+static unsigned char *buf;
 static int head, left;
 static int count;
 static struct termios termios;
@@ -46,7 +47,7 @@ static void draw(void)
 	int i, j;
 	for (i = rs; i < re; i++) {
 		for (j = cs; j < ce; j++) {
-			unsigned char *src = (void *) (buf + (i * cols + j) * ch);
+			unsigned char *src = buf + (i * cols + j) * ch;
 			unsigned int *dst = (void *) (row + (j - cs) * bpp);
 			*dst = FB_VAL(src[0], src[1], src[2]);
 		}
@@ -67,7 +68,7 @@ static void drawfs(void)
 			memset(row, 0, fb_cols() * bpp);
 		for (j = 0; j < fb_cols() && r < rows; j++) {
 			int c = j * cols / fb_cols();
-			unsigned char *src = (void *) (buf + (r * cols + c) * ch);
+			unsigned char *src = buf + (r * cols + c) * ch;
 			unsigned int *dst = (void *) (row + j * bpp);
 			*dst = FB_VAL(src[0], src[1], src[2]);
 		}
@@ -76,25 +77,18 @@ static void drawfs(void)
 }
 
 unsigned char *stbi_load(char const *filename, int *x, int *y, int *comp, int req_comp);
-
-static char *loadstbi(char *path, int *h, int *w, int *ch)
-{
-	return (void *) stbi_load(path, w, h, ch, 0);
-}
-
-static char *loadlode(char *path, int *h, int *w, int *ch)
-{
-	char *s = NULL;
-	*ch = 4;
-	lodepng_decode32_file((void *) &s, (void *) w, (void *) h, path);
-	return s;
-}
+char *ppm_load(char *path, int *h, int *w);
 
 static int loadfile(char *path)
 {
-	buf = loadlode(path, &rows, &cols, &ch);
+	ch = 4;
+	lodepng_decode32_file(&buf, (void *) &cols, (void *) &rows, path);
 	if (!buf)
-		buf = loadstbi(path, &rows, &cols, &ch);
+		buf = stbi_load(path, &cols, &rows, &ch, 0);
+	if (!buf) {
+		ch = 3;
+		buf = (void *) ppm_load(path, &rows, &cols);
+	}
 	return !buf;
 }
 
diff --git a/ppm.c b/ppm.c
new file mode 100644
index 0000000..c9d8840
--- /dev/null
+++ b/ppm.c
@@ -0,0 +1,56 @@
+#include <ctype.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+static int nextchar(int fd)
+{
+	unsigned char b[4] = {0};
+	read(fd, b, 1);
+	return b[0];
+}
+
+static int cutint(int fd)
+{
+	int c;
+	int n = 0;
+	do {
+		c = nextchar(fd);
+	} while (isspace(c));
+	while (isdigit(c)) {
+		n = n * 10 + c - '0';
+		c = nextchar(fd);
+	}
+	return n;
+}
+
+char *ppm_load(char *path, int *h, int *w)
+{
+	char *d;
+	int fd = open(path, O_RDONLY);
+	if (fd < 0 || nextchar(fd) != 'P' || nextchar(fd) != '6')
+		return NULL;
+	*w = cutint(fd);	/* image width */
+	*h = cutint(fd);	/* image height */
+	cutint(fd);		/* max color val */
+
+	d = malloc(*h * *w * 3); 
+	read(fd, d, *h * *w * 3);
+	close(fd);
+	return d;
+}
+
+void ppm_save(char *path, char *s, int h, int w)
+{
+	char sig[128];
+	int fd;
+	sprintf(sig, "P6\n%d %d\n255\n", w, h);
+	fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, 0600);
+	write(fd, sig, strlen(sig));
+	write(fd, s, h * w * 3);
+	close(fd);
+}
-- 
2.11.4.GIT