# HG changeset patch
# User John Tsiombikas <nuclear@member.fsf.org>
# Date 1457848563 -7200
# Node ID d3f2a2b19504d6d6ca6f668cda74a38a11b3e8fd
# Parent  a5755687dd7523f2f9c8394e4de67ea2caf5ac1b
doorbell server under construction

diff -r a5755687dd75 -r d3f2a2b19504 .hgignore
--- a/.hgignore	Tue Mar 08 03:26:01 2016 +0200
+++ b/.hgignore	Sun Mar 13 07:56:03 2016 +0200
@@ -2,3 +2,5 @@
 \.d$
 \.swp$
 spycam$
+doorbelld$
+\.ppm$
diff -r a5755687dd75 -r d3f2a2b19504 doorbelld/Makefile
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/doorbelld/Makefile	Sun Mar 13 07:56:03 2016 +0200
@@ -0,0 +1,13 @@
+src = $(wildcard src/*.c)
+obj = $(src:.c=.o)
+bin = doorbelld
+
+CFLAGS = -pedantic -Wall -g
+LDFLAGS = -lwcam -lpthread
+
+$(bin): $(obj)
+	$(CC) -o $@ $(obj) $(LDFLAGS)
+
+.PHONY: clean
+clean:
+	rm -f $(obj) $(bin)
diff -r a5755687dd75 -r d3f2a2b19504 doorbelld/src/dynarr.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/doorbelld/src/dynarr.c	Sun Mar 13 07:56:03 2016 +0200
@@ -0,0 +1,128 @@
+/* dynarr - dynamic resizable C array data structure
+ * author: John Tsiombikas <nuclear@member.fsf.org>
+ * license: public domain
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "dynarr.h"
+
+/* The array descriptor keeps auxilliary information needed to manipulate
+ * the dynamic array. It's allocated adjacent to the array buffer.
+ */
+struct arrdesc {
+	int nelem, szelem;
+	int max_elem;
+	int bufsz;	/* not including the descriptor */
+};
+
+#define DESC(x)		((struct arrdesc*)((char*)(x) - sizeof(struct arrdesc)))
+
+void *dynarr_alloc(int elem, int szelem)
+{
+	struct arrdesc *desc;
+
+	if(!(desc = malloc(elem * szelem + sizeof *desc))) {
+		return 0;
+	}
+	desc->nelem = desc->max_elem = elem;
+	desc->szelem = szelem;
+	desc->bufsz = elem * szelem;
+	return (char*)desc + sizeof *desc;
+}
+
+void dynarr_free(void *da)
+{
+	if(da) {
+		free(DESC(da));
+	}
+}
+
+void *dynarr_resize(void *da, int elem)
+{
+	int newsz;
+	void *tmp;
+	struct arrdesc *desc;
+
+	if(!da) return 0;
+	desc = DESC(da);
+
+	newsz = desc->szelem * elem;
+
+	if(!(tmp = realloc(desc, newsz + sizeof *desc))) {
+		return 0;
+	}
+	desc = tmp;
+
+	desc->nelem = desc->max_elem = elem;
+	desc->bufsz = newsz;
+	return (char*)desc + sizeof *desc;
+}
+
+int dynarr_empty(void *da)
+{
+	return DESC(da)->nelem ? 0 : 1;
+}
+
+int dynarr_size(void *da)
+{
+	return DESC(da)->nelem;
+}
+
+
+/* stack semantics */
+void *dynarr_push(void *da, void *item)
+{
+	struct arrdesc *desc;
+	int nelem;
+
+	desc = DESC(da);
+	nelem = desc->nelem;
+
+	if(nelem >= desc->max_elem) {
+		/* need to resize */
+		struct arrdesc *tmp;
+		int newsz = desc->max_elem ? desc->max_elem * 2 : 1;
+
+		if(!(tmp = dynarr_resize(da, newsz))) {
+			fprintf(stderr, "failed to resize\n");
+			return da;
+		}
+		da = tmp;
+		desc = DESC(da);
+		desc->nelem = nelem;
+	}
+
+	if(item) {
+		memcpy((char*)da + desc->nelem++ * desc->szelem, item, desc->szelem);
+	}
+	return da;
+}
+
+void *dynarr_pop(void *da)
+{
+	struct arrdesc *desc;
+	int nelem;
+
+	desc = DESC(da);
+	nelem = desc->nelem;
+
+	if(!nelem) return da;
+
+	if(nelem <= desc->max_elem / 3) {
+		/* reclaim space */
+		struct arrdesc *tmp;
+		int newsz = desc->max_elem / 2;
+
+		if(!(tmp = dynarr_resize(da, newsz))) {
+			fprintf(stderr, "failed to resize\n");
+			return da;
+		}
+		da = tmp;
+		desc = DESC(da);
+		desc->nelem = nelem;
+	}
+	desc->nelem--;
+
+	return da;
+}
diff -r a5755687dd75 -r d3f2a2b19504 doorbelld/src/dynarr.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/doorbelld/src/dynarr.h	Sun Mar 13 07:56:03 2016 +0200
@@ -0,0 +1,38 @@
+/* dynarr - dynamic resizable C array data structure
+ * author: John Tsiombikas <nuclear@member.fsf.org>
+ * license: public domain
+ */
+#ifndef DYNARR_H_
+#define DYNARR_H_
+
+void *dynarr_alloc(int elem, int szelem);
+void dynarr_free(void *da);
+void *dynarr_resize(void *da, int elem);
+
+int dynarr_empty(void *da);
+int dynarr_size(void *da);
+
+/* stack semantics */
+void *dynarr_push(void *da, void *item);
+void *dynarr_pop(void *da);
+
+
+/* usage example:
+ * -------------
+ * int *arr = dynarr_alloc(0, sizeof *arr);
+ *
+ * int x = 10;
+ * arr = dynarr_push(arr, &x);
+ * x = 5;
+ * arr = dynarr_push(arr, &x);
+ * x = 42;
+ * arr = dynarr_push(arr, &x);
+ *
+ * for(i=0; i<dynarr_size(arr); i++) {
+ *     printf("%d\n", arr[i]);
+ *  }
+ *  dynarr_free(arr);
+ */
+
+
+#endif	/* DYNARR_H_ */
diff -r a5755687dd75 -r d3f2a2b19504 doorbelld/src/main.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/doorbelld/src/main.c	Sun Mar 13 07:56:03 2016 +0200
@@ -0,0 +1,141 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <signal.h>
+#include <pthread.h>
+#include <wcam.h>
+#include "srv.h"
+
+void *frame_proc(void *arg);
+int save_image(const char *fname, unsigned char *pixels, int xsz, int ysz);
+void sighandler(int s);
+
+int fd;
+int width = 640;
+int height = 480;
+int framerate = 30;
+unsigned char *frame;
+int done;
+int frame_available;
+pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
+pthread_cond_t condvar = PTHREAD_COND_INITIALIZER;
+
+int main(int argc, char **argv)
+{
+	char *devfile = "/dev/video0";
+	pthread_t thread;
+
+	if(argv[1]) {
+		devfile = argv[1];
+	}
+
+	signal(SIGINT, sighandler);
+	signal(SIGQUIT, sighandler);
+	signal(SIGSEGV, sighandler);
+
+	if(srv_init(2828) == -1) {
+		return 1;
+	}
+
+	if(!(frame = malloc(width * height * 4))) {
+		perror("failed to allocate frame");
+		return 1;
+	}
+
+	if((fd = wcam_open(devfile, width, height, framerate)) == -1) {
+		fprintf(stderr, "failed to open video device: %s\n", devfile);
+		return 1;
+	}
+	wcam_start(fd);
+
+	if(pthread_create(&thread, 0, frame_proc, 0) == -1) {
+		fprintf(stderr, "failed to create frame processing thread\n");
+		return 1;
+	}
+
+	while(!done) {
+		int i, res;
+		int *sock = srv_sockets();
+		int num_sockets = srv_num_sockets();
+		int maxfd = srv_max_socket();
+		fd_set rdset;
+
+		if(fd > maxfd) maxfd = fd;
+
+		FD_ZERO(&rdset);
+		FD_SET(fd, &rdset);
+
+		for(i=0; i<num_sockets; i++) {
+			FD_SET(sock[i], &rdset);
+		}
+
+		while((res = select(maxfd + 1, &rdset, 0, 0, 0)) == -1 && errno == EINTR);
+		if(res == -1) {
+			fprintf(stderr, "unexpected failure while waiting for I/O\n");
+			break;
+		}
+
+		if(FD_ISSET(fd, &rdset)) {
+			wcam_wait(fd);
+			pthread_mutex_lock(&mutex);
+			frame_available = 1;
+			pthread_mutex_unlock(&mutex);
+			pthread_cond_signal(&condvar);
+		}
+
+		for(i=0; i<num_sockets; i++) {
+			if(FD_ISSET(sock[i], &rdset)) {
+				srv_handle(sock[i]);
+			}
+		}
+	}
+
+	frame_available = 1;
+	pthread_cond_signal(&condvar);
+	pthread_join(thread, 0);
+	free(frame);
+	wcam_stop(fd);
+	wcam_close(fd);
+	return 0;
+}
+
+void *frame_proc(void *arg)
+{
+	for(;;) {
+		pthread_mutex_lock(&mutex);
+		while(!frame_available) {
+			pthread_cond_wait(&condvar, &mutex);
+		}
+		frame_available = 0;
+		pthread_mutex_unlock(&mutex);
+
+		if(done) break;
+
+		wcam_read_frame_rgb(fd, frame);
+		save_image("output.ppm", frame, width, height);
+	}
+	return 0;
+}
+
+int save_image(const char *fname, unsigned char *pixels, int xsz, int ysz)
+{
+	int i, num_pixels = xsz * ysz;
+	FILE *fp = fopen(fname, "wb");
+	if(!fp) return -1;
+
+	fprintf(fp, "P6\n%d %d\n255\n", xsz, ysz);
+	for(i=0; i<num_pixels; i++) {
+		fputc(*pixels++, fp);
+		fputc(*pixels++, fp);
+		fputc(*pixels++, fp);
+		++pixels;
+	}
+	fclose(fp);
+	return 0;
+}
+
+void sighandler(int s)
+{
+	done = 1;
+}
diff -r a5755687dd75 -r d3f2a2b19504 doorbelld/src/srv.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/doorbelld/src/srv.c	Sun Mar 13 07:56:03 2016 +0200
@@ -0,0 +1,123 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <assert.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/socket.h>
+#include <arpa/inet.h>
+#include "srv.h"
+#include "dynarr.h"
+
+static int lis_sock = -1, max_socket = -1;
+static int *csock;
+
+int srv_init(int port)
+{
+	struct sockaddr_in addr;
+
+	if(lis_sock != -1) {
+		fprintf(stderr, "%s: already running\n", __func__);
+		return -1;
+	}
+
+	if((lis_sock = socket(PF_INET, SOCK_STREAM, 0)) == -1) {
+		fprintf(stderr, "%s: failed to create listening socket\n", __func__);
+		return -1;
+	}
+	if(!(csock = dynarr_alloc(1, sizeof *csock))) {
+		fprintf(stderr, "%s: failed to allocate client socket array\n", __func__);
+		return -1;
+	}
+	csock[0] = lis_sock;
+	max_socket = lis_sock;
+
+	fcntl(lis_sock, F_SETFD, fcntl(lis_sock, F_GETFD) | O_NONBLOCK);
+
+	memset(&addr, 0, sizeof addr);
+	addr.sin_family = AF_INET;
+	addr.sin_port = htons(port);
+	addr.sin_addr.s_addr = INADDR_ANY;
+	if(bind(lis_sock, (struct sockaddr*)&addr, sizeof addr) == -1) {
+		fprintf(stderr, "%s: failed to bind port %d\n", __func__, port);
+		close(lis_sock);
+		lis_sock = -1;
+		return -1;
+	}
+
+	return 0;
+}
+
+void srv_shutdown(void)
+{
+	int i, sz = dynarr_size(csock);
+	for(i=0; i<sz; i++) {
+		close(csock[i]);
+	}
+	dynarr_free(csock);
+	csock = 0;
+	lis_sock = -1;
+	max_socket = -1;
+}
+
+int srv_num_sockets(void)
+{
+	return dynarr_size(csock);
+}
+
+int *srv_sockets(void)
+{
+	return csock;
+}
+
+int srv_max_socket(void)
+{
+	return max_socket;
+}
+
+int srv_handle(int s)
+{
+	static char buf[1024];
+	int sz;
+
+	if(s == lis_sock) {
+		/* incoming connection */
+		struct sockaddr_in addr;
+		int addr_size;
+
+		if((s = accept(lis_sock, (struct sockaddr*)&addr, (int*)&addr_size)) == -1) {
+			fprintf(stderr, "%s: failed to accept incoming connection\n", __func__);
+			return -1;
+		}
+		printf("%s: incoming connection from %s:%d\n", __func__,
+				inet_ntoa(addr.sin_addr), ntohs(addr.sin_port));
+		csock = dynarr_push(csock, &s);
+		assert(csock);
+		return 0;
+	}
+
+	/* handle client */
+	while((sz = read(s, buf, sizeof buf - 1)) > 0) {
+		printf("%s: got data: %s\n", __func__, buf);
+	}
+	if(sz < 0 && errno != EAGAIN) {
+		/* client closed connection probably */
+		int i, num_clients = dynarr_size(csock);
+		printf("%s: removing client\n", __func__);
+		close(s);
+		for(i=0; i<num_clients; i++) {
+			if(csock[i] == s) {
+				csock[i] = csock[num_clients - 1];
+				csock = dynarr_pop(csock);
+				break;
+			}
+		}
+		assert(i < num_clients);
+	}
+	return 0;
+}
+
+void srv_send_frame(unsigned char *frame, int xsz, int ysz)
+{
+}
diff -r a5755687dd75 -r d3f2a2b19504 doorbelld/src/srv.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/doorbelld/src/srv.h	Sun Mar 13 07:56:03 2016 +0200
@@ -0,0 +1,15 @@
+#ifndef SRV_H_
+#define SRV_H_
+
+int srv_init(int port);
+void srv_shutdown(void);
+
+int srv_num_sockets(void);
+int *srv_sockets(void);
+int srv_max_socket(void);
+
+int srv_handle(int s);
+
+void srv_send_frame(unsigned char *frame, int xsz, int ysz);
+
+#endif	/* SRV_H_ */