http server: don't assume multipart/x-mixed-replace streams are JPEGs

7 files changed, 88 insertions, 71 deletions

diff --git a/.gitignore b/.gitignore
index db97f5f..2e01979 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,6 +1,6 @@
 /freenect-server
 /freenect-server--kinect
-/freenect-server--http
+/multipart-replace-http-server
 
 *.o
 .*.mk
\ No newline at end of file
diff --git a/Makefile b/Makefile
index 3a54db5..5ae2d4b 100644
--- a/Makefile
+++ b/Makefile
@@ -4,14 +4,14 @@ CFLAGS += -g -std=c99 -Wall -Werror -Wextra -pedantic
 CPPFLAGS += -std=c99 -Wall -Werror -Wextra -pedantic
 CPPFLAGS += -D_GNU_SOURCE
 
-all: freenect-server freenect-server--kinect freenect-server--http
+all: freenect-server freenect-server--kinect multipart-replace-http-server
 .PHONY: all
 
 freenect-server--kinect: util.o -lfreenect -lusb-1.0
-freenect-server--http: util.o mpjpeg.o -lpthread
+multipart-replace-http-server: util.o multipart-replace.o -lpthread
 
 clean:
-	rm -f -- *.o .*.mk freenect-server freenect-server--kinect freenect-server--http
+	rm -f -- *.o .*.mk freenect-server freenect-server--kinect multipart-replace-http-server
 .PHONY: clean
 
 .DELETE_ON_ERROR:
diff --git a/freenect-server.sh b/freenect-server.sh
index 27d3fd3..721243c 100644
--- a/freenect-server.sh
+++ b/freenect-server.sh
@@ -11,7 +11,7 @@ mkfifo $t/video.mjpg
 mkfifo $t/depth.mjpg
 
 ( freenect-server--kinect -v $t/video.rgb24 -d $t/depth.rgb24; echo "EXITED: freenect-server--kinect: $?") & pids+=($!)
-( freenect-server--http 5800 $t/video.mjpg $t/depth.mjpg; echo "EXITED: freenect-server--http: $?") & pids+=($!)
+( multipart-replace-http-server 5800 $t/video.mjpg $t/depth.mjpg; echo "EXITED: freenect-server--http: $?") & pids+=($!)
 rm -f {depth,video}.{avi,mjpg}
 ( ffmpeg -loglevel warning -pixel_format rgb24 -s 640x480 -f rawvideo -i $t/video.rgb24 -q:v 1 -f mpjpeg - > $t/video.mjpg; echo "EXITED: ffmpeg video: $?") & pids+=($!)
 ( ffmpeg -loglevel warning -pixel_format rgb24 -s 640x480 -f rawvideo -i $t/depth.rgb24 -q:v 1 -f mpjpeg - > $t/depth.mjpg; echo "EXITED: ffmpeg depth: $?") & pids+=($!)
diff --git a/mpjpeg.h b/mpjpeg.h
deleted file mode 100644
index f850adc..0000000
--- a/mpjpeg.h
+++ /dev/null
@@ -1,22 +0,0 @@
-/* Copyright 2016 Luke Shumaker */
-
-#pragma once
-
-#include <pthread.h>
-
-struct frame {
-	ssize_t len;
-	size_t cap;
-	char *data;
-};
-
-struct mpjpeg_stream {
-	struct frame a, b;
-	struct frame *front, *back;
-	pthread_rwlock_t frontlock;
-	long framecount;
-};
-
-void mpjpeg_reader(struct mpjpeg_stream *s, int fd, const char *boundary);
-void mpjpeg_writer(struct mpjpeg_stream *s, int fd, const char *boundary);
-void init_mpjpeg_stream();
diff --git a/freenect-server--http.c b/multipart-replace-http-server.c
index cda7ae1..c3e6219 100644
--- a/freenect-server--http.c
+++ b/multipart-replace-http-server.c
@@ -11,30 +11,30 @@
 #include <fcntl.h> /* for open */
 
 #include "util.h"
-#include "mpjpeg.h"
+#include "multipart-replace.h"
 
 struct httpfile {
 	char name[256];
-	struct mpjpeg_stream *stream;
+	struct multipart_replace_stream *stream;
 };
 
 size_t filec = 0;
 struct httpfile *filev = NULL;
 
 struct reader_thread_args {
-	struct mpjpeg_stream *stream;
+	struct multipart_replace_stream *stream;
 	int fd;
 	const char *boundary;
 };
 
 void *reader_thread(void *args_anon) {
 	struct reader_thread_args *args = args_anon;
-	mpjpeg_reader(args->stream, args->fd, args->boundary);
-	error(EXIT_FAILURE, 0, "mpjpeg stream ended");
+	multipart_replace_reader(args->stream, args->fd, args->boundary);
+	error(EXIT_FAILURE, 0, "multipart_replace stream ended");
 	return NULL;
 }
 
-void start_mpjpeg_reader(struct mpjpeg_stream *s, int fd, const char *boundary) {
+void start_multipart_replace_reader(struct multipart_replace_stream *s, int fd, const char *boundary) {
 	struct reader_thread_args *args = xrealloc(NULL, sizeof(struct reader_thread_args));
 	args->stream = s;
 	args->fd = fd;
@@ -44,8 +44,8 @@ void start_mpjpeg_reader(struct mpjpeg_stream *s, int fd, const char *boundary)
 }
 
 void file_add(const char *filename) {
-	struct mpjpeg_stream *stream = xrealloc(NULL, sizeof(struct mpjpeg_stream));
-	init_mpjpeg_stream(stream);
+	struct multipart_replace_stream *stream = xrealloc(NULL, sizeof(struct multipart_replace_stream));
+	init_multipart_replace_stream(stream);
 	int fd = open(filename, O_RDONLY);
 	if (fd < 0)
 		error(EXIT_FAILURE, errno, "opening file: %s", filename);
@@ -56,10 +56,10 @@ void file_add(const char *filename) {
 	strncpy(filev[filec-1].name, shortname, sizeof(filev[filec-1].name));
 	error(0, 0, "added file #%zd: %s", filec-1, filev[filec-1].name);
 	filev[filec-1].stream = stream;
-	start_mpjpeg_reader(stream, fd, "ffserver" /* FIXME */);
+	start_multipart_replace_reader(stream, fd, "ffserver" /* FIXME */);
 }
 
-struct mpjpeg_stream *file_get(const char *filename) {
+struct multipart_replace_stream *file_get(const char *filename) {
 	for (size_t i = 0; i < filec; i++) {
 		if (strncmp(filename, filev[i].name, sizeof(filev[i].name)) == 0) {
 			return filev[i].stream;
@@ -124,7 +124,7 @@ void connection_handler(int fd) {
 	while (strcmp(line_buf, "\r\n") != 0 && line_len >= 0)
 		line_len = getline(&line_buf, &line_cap, netstream);
 
-	struct mpjpeg_stream *vidstream = file_get(path);
+	struct multipart_replace_stream *vidstream = file_get(path);
 	if (vidstream == NULL) {
 		error(0, 0, "404 %s", path);
 		dprintf(fd,
@@ -140,7 +140,7 @@ void connection_handler(int fd) {
 	        "Content-Type: multipart/x-mixed-replace;boundary=%s\r\n"
 	        "\r\n",
 	        boundary);
-	mpjpeg_writer(vidstream, fd, boundary);
+	multipart_replace_writer(vidstream, fd, boundary);
 	close(fd);
 }
 
diff --git a/mpjpeg.c b/multipart-replace.c
index 87ca2a4..30ae7bb 100644
--- a/mpjpeg.c
+++ b/multipart-replace.c
@@ -7,7 +7,7 @@
 #include <string.h>
 #include <unistd.h>
 
-#include "mpjpeg.h"
+#include "multipart-replace.h"
 #include "util.h"
 
 static
@@ -38,44 +38,53 @@ ssize_t safe_atoi(char *str) {
 	return atoi(str);
 }
 
-void mpjpeg_reader(struct mpjpeg_stream *s, int fd, const char *boundary) {
+#define rgetline() do { if ((line_len = getline(&line_buf, &line_cap, stream)) < 0) { error(0, 0, "source hung up"); return; } } while(0)
+void multipart_replace_reader(struct multipart_replace_stream *s, int fd, const char *boundary) {
 	FILE *stream = fdopen(fd, "r");
 	boundary = boundary_line(boundary);
 
 	char *line_buf = NULL;
 	size_t line_cap = 0;
 	ssize_t line_len = 0;
+	ssize_t content_length = -1;
 
 	while (1) {
-		s->back->len = -1;
+		content_length = -1;
 		/* scan for the first non-empty line */
 		do {
-			line_len = getline(&line_buf, &line_cap, stream);
-		} while (line_len >= 0 && strcmp(line_buf, "\r\n") == 0);
+			rgetline();
+		} while (strcmp(line_buf, "\r\n") == 0);
 		/* make sure it matches the boundary separator */
 		if (strcmp(line_buf, boundary) != 0) {
 			error(0, 0, "line does not match boundary: \"%s\"", line_buf);
 			return;
 		}
 		/* read the frame header (MIME headers) */
-		while (strcmp(line_buf, "\r\n") != 0 && line_len >= 0) {
-			line_len = getline(&line_buf, &line_cap, stream);
+		do {
+			rgetline();
+			/* append the line to the frame contents */
+			if ((ssize_t)s->back->cap < s->back->len + line_len)
+				s->back->buf = xrealloc(s->back->buf, s->back->cap = s->back->len + line_len);
+			memcpy(&s->back->buf[s->back->len], line_buf, line_len);
+			s->back->len += line_len;
+			/* parse the Content-length (if applicable) */
 			if (strncasecmp(line_buf, "Content-length:", strlen("Content-length:")) == 0) {
-				s->back->len = safe_atoi(&line_buf[strlen("Content-length:")]);
+				content_length = safe_atoi(&line_buf[strlen("Content-length:")]);
 			}
-		}
-		if (s->back->len < 0) {
+		} while (strcmp(line_buf, "\r\n") != 0);
+		/* make sure that it included a Content-length header */
+		if (content_length < 0) {
 			error(0, 0, "did not get frame length");
 			return;
 		}
-
-		/* read the frame contents (JPEG) */
-		if (s->back->cap < (size_t)s->back->len)
-			s->back->data = xrealloc(s->back->data, s->back->cap = s->back->len);
-		if (fread(s->back->data, s->back->len, 1, stream) != 1) {
+		/* read the frame contents */
+		if ((ssize_t)s->back->cap < s->back->len + content_length)
+			s->back->buf = xrealloc(s->back->buf, s->back->cap = s->back->len + content_length);
+		if (fread(s->back->buf, s->back->len, 1, stream) != 1) {
 			error(0, ferror(stream), "fread(%zd)", s->back->len);
 			return;
 		}
+		s->back->len += content_length;
 
 		/* swap the frames */
 		pthread_rwlock_wrlock(&s->frontlock);
@@ -85,41 +94,49 @@ void mpjpeg_reader(struct mpjpeg_stream *s, int fd, const char *boundary) {
 		s->framecount++;
 		pthread_rwlock_unlock(&s->frontlock);
 	}
-
 }
 
-void mpjpeg_writer(struct mpjpeg_stream *s, int fd, const char *boundary) {
+void multipart_replace_writer(struct multipart_replace_stream *s, int fd, const char *boundary) {
 	struct frame myframe = { 0 };
 	long lastframe = 0;
-	pthread_rwlock_rdlock(&s->frontlock);
+	boundary = boundary_line(boundary);
+	size_t boundary_len = strlen(boundary);
+
 	while(1) {
-		/* get the most recent frame (copy front to myframe) */
+		/* poll until there's a new frame */
+		pthread_rwlock_rdlock(&s->frontlock);
+		while (s->framecount == lastframe) {
+			pthread_rwlock_unlock(&s->frontlock);
+			usleep(30000); /* a bit over 30 FPS */
+			pthread_rwlock_rdlock(&s->frontlock);
+		}
+
+		/* get the most recent frame (copy `s->front` to `myframe`) */
 		if (myframe.cap < (size_t)s->front->len)
-			myframe.data = xrealloc(myframe.data, myframe.cap = s->front->len);
-		memcpy(myframe.data, s->front->data, myframe.len = s->front->len);
+			myframe.buf = xrealloc(myframe.buf, myframe.cap = s->front->len);
+		memcpy(myframe.buf, s->front->buf, myframe.len = s->front->len);
 		lastframe = s->framecount;
+
 		pthread_rwlock_unlock(&s->frontlock);
+
 		/* send the frame to the client */
-		if (dprintf(fd, "--%s\r\nContent-Type: image/jpeg\r\nContent-Length: %zd\r\n\r\n", boundary, myframe.len) < 0) {
-			error(0, errno, "dprintf");
+		if (write(fd, boundary, boundary_len) < (ssize_t)boundary_len) {
+			error(0, errno, "write");
 			return;
 		}
-		if (write(fd, myframe.data, myframe.len) < myframe.len) {
+		if (write(fd, myframe.buf, myframe.len) < myframe.len) {
 			error(0, errno, "write");
 			return;
 		}
-
-		/* poll until there's a new frame */
-		pthread_rwlock_rdlock(&s->frontlock);
-		while (s->framecount == lastframe) {
-			pthread_rwlock_unlock(&s->frontlock);
-			usleep(30000); /* a bit over 30 FPS */
-			pthread_rwlock_rdlock(&s->frontlock);
+		/* send a blank line for pleasantness */
+		if (write(fd, "\r\n", 2) < 2) {
+			error(0, errno, "write");
+			return;
 		}
 	}
 }
 
-void init_mpjpeg_stream(struct mpjpeg_stream *s) {
+void init_multipart_replace_stream(struct multipart_replace_stream *s) {
 	ZERO(s->a);
 	ZERO(s->b);
 	s->front = &s->a;
diff --git a/multipart-replace.h b/multipart-replace.h
new file mode 100644
index 0000000..126f6fa
--- /dev/null
+++ b/multipart-replace.h
@@ -0,0 +1,22 @@
+/* Copyright 2016 Luke Shumaker */
+
+#pragma once
+
+#include <pthread.h>
+
+struct frame {
+	ssize_t len;
+	size_t cap;
+	char *buf;
+};
+
+struct multipart_replace_stream {
+	struct frame a, b;
+	struct frame *front, *back;
+	pthread_rwlock_t frontlock;
+	long framecount;
+};
+
+void multipart_replace_reader(struct multipart_replace_stream *s, int fd, const char *boundary);
+void multipart_replace_writer(struct multipart_replace_stream *s, int fd, const char *boundary);
+void init_multipart_replace_stream();