Send png images

2 files changed, 217 insertions, 174 deletions

diff --git a/client.html b/client.html
index e31422e..2637ad7 100644
--- a/client.html
+++ b/client.html
@@ -66,6 +66,22 @@ function handleLoad(event)
   i = 0;
   while (i < cmd.length) {
     switch (cmd[i]) {
+      case 'i':
+        i++;
+        x = base64_16(cmd, i);
+        i = i + 3;
+        y = base64_16(cmd, i);
+        i = i + 3;
+        size = base64_32(cmd, i);
+        i = i + 6;
+	url = cmd.slice(i, i + size);
+	i = i + size;
+        var img = new Image();
+	img.src = url
+        context.drawImage(img, x, y);
+
+        break;
+
       case 'b':
         i++;
         sx = base64_16(cmd, i);
@@ -80,7 +96,9 @@ function handleLoad(event)
         i = i + 3;
         dy = base64_16(cmd, i);
         i = i + 3;
-        context.drawImage(canvas, sx, sy, w, h, dx, dy, w, h)
+        context.drawImage(canvas, sx, sy, w, h, dx, dy, w, h);
+
+        break;
 
       case 'r':
         i++;
diff --git a/daemon.c b/daemon.c
index ad4687f..126c270 100644
--- a/daemon.c
+++ b/daemon.c
@@ -100,6 +100,200 @@ send_copyrect (GOutputStream *out,  int sx, int sy, int w, int h, int dx, int dy
 			     NULL, NULL, NULL);
 }
 
+/* Table of CRCs of all 8-bit messages. */
+static unsigned long crc_table[256];
+
+/* Flag: has the table been computed? Initially false. */
+static int crc_table_computed = 0;
+
+/* Make the table for a fast CRC. */
+static void
+make_crc_table(void)
+{
+  unsigned long c;
+  int n, k;
+
+  for (n = 0; n < 256; n++) {
+    c = (unsigned long) n;
+    for (k = 0; k < 8; k++) {
+      if (c & 1)
+	c = 0xedb88320L ^ (c >> 1);
+      else
+	c = c >> 1;
+    }
+    crc_table[n] = c;
+  }
+  crc_table_computed = 1;
+}
+
+static unsigned long
+update_crc(unsigned long crc, unsigned char *buf, int len)
+{
+  unsigned long c = crc;
+  int n;
+
+  if (!crc_table_computed)
+    make_crc_table();
+  for (n = 0; n < len; n++) {
+    c = crc_table[(c ^ buf[n]) & 0xff] ^ (c >> 8);
+  }
+  return c;
+}
+
+static unsigned long
+crc(unsigned char *buf, int len)
+{
+  return update_crc(0xffffffffL, buf, len) ^ 0xffffffffL;
+}
+
+#define BASE 65521 /* largest prime smaller than 65536 */
+static unsigned long
+update_adler32(unsigned long adler, unsigned char *buf, int len)
+{
+  unsigned long s1 = adler & 0xffff;
+  unsigned long s2 = (adler >> 16) & 0xffff;
+  int n;
+
+  for (n = 0; n < len; n++) {
+    s1 = (s1 + buf[n]) % BASE;
+    s2 = (s2 + s1)     % BASE;
+  }
+  return (s2 << 16) + s1;
+}
+
+char *
+to_png_rgb (int w, int h, int stride, guint32 *data)
+{
+  guchar header[] = {137, 80, 78, 71, 13, 10, 26, 10};
+  guchar ihdr[13+12] = {0, 0, 0, 13, 'I', 'H', 'D', 'R',
+			/* w: */ 0, 0, 0, 0, /* h: */ 0,0,0,0,
+			/* bpp: */ 8, /* color type: */ 2,
+			0, 0, 0};
+  guchar idat_start[8] = { /* len: */0, 0, 0, 0,   'I', 'D', 'A', 'T' };
+  guchar iend[12] = {0, 0, 0, 0, 'I', 'E', 'N', 'D', 0xae, 0x42, 0x60, 0x82};
+  gsize data_size, row_size;
+  char row_header[6];
+  guint8 *png, *p, *p_row, *p_idat;
+  guint32 *row;
+  unsigned long adler;
+  guint32 pixel;
+  gsize png_size;
+  int x, y;
+  char *url, *url_base64;
+  gint state = 0, outlen;
+  gint save = 0;
+
+  *(guint32 *)&ihdr[8] = GUINT32_TO_BE(w);
+  *(guint32 *)&ihdr[12] = GUINT32_TO_BE(h);
+  *(guint32 *)&ihdr[21] = GUINT32_TO_BE(crc(&ihdr[4], 13 + 4));
+
+  row_size = 1 + w * 3;
+  row_header[0] = 0;
+  row_header[1] = row_size & 0xff;
+  row_header[2] = (row_size >> 8) & 0xff;
+  row_header[3] = ~row_header[1];
+  row_header[4] = ~row_header[2];
+  row_header[5] = 0;
+
+  data_size = 2 + (6 + w * 3) * h + 4;
+
+  *(guint32 *)&idat_start[0] = GUINT32_TO_BE(data_size);
+
+  png_size = sizeof(header) + sizeof(ihdr) + 12 + data_size + sizeof(iend);
+  png = g_malloc (png_size);
+
+  p = png;
+  memcpy (p, header, sizeof(header));
+  p += sizeof(header);
+  memcpy (p, ihdr, sizeof(ihdr));
+  p += sizeof(ihdr);
+  memcpy (p, idat_start, sizeof(idat_start));
+  p += sizeof(idat_start);
+
+  /* IDAT data:
+
+     zlib header:  0x78, 0x01 ,
+     h * scanline: row_header[] + width * r,g,b
+     checksum: adler32
+  */
+
+  p_idat = p - 4;
+
+  /* zlib header */
+  *p++ = 0x78;
+  *p++ = 0x01;
+
+  adler = 1;
+
+  /* scanline data */
+  for (y = 0; y < h; y++) {
+    if (y == h - 1)
+      row_header[0] = 1; /* final block */
+    memcpy (p, row_header, sizeof(row_header));
+    p += sizeof(row_header);
+    p_row = p - 1;
+    row = data;
+    data += stride;
+    for (x = 0; x < w; x++) {
+      pixel = *row++;
+      *p++ = (pixel >> 16) & 0xff; /* red */
+      *p++ = (pixel >> 8) & 0xff; /* green */
+      *p++ = (pixel >> 0) & 0xff; /* blue */
+    }
+    adler = update_adler32(adler, p_row, p - p_row);
+  }
+
+  /* adler32 */
+  *(guint32 *)p = GUINT32_TO_BE(adler);
+  p += 4;
+  *(guint32 *)p = GUINT32_TO_BE(crc(p_idat, p - p_idat));
+  p += 4;
+
+  memcpy (p, iend, sizeof(iend));
+  p += sizeof(iend);
+
+  g_assert(p - png == png_size);
+
+  url = g_malloc (strlen("data:image/png;base64,") +
+		  ((png_size / 3 + 1) * 4 + 4) + 1);
+  strcpy (url, "data:image/png;base64,");
+
+  url_base64 = url + strlen("data:image/png;base64,");
+  outlen = g_base64_encode_step (png, png_size, FALSE, url_base64, &state, &save);
+  outlen += g_base64_encode_close (FALSE, url_base64 + outlen, &state, &save);
+  url_base64[outlen] = 0;
+
+  g_free (png);
+
+  return url;
+}
+
+static void
+send_image_rgb (GOutputStream *out,  int x, int y,
+		int w, int h, int stride, guint32 *data)
+{
+  char buf[13];
+  gsize len;
+  char *url;
+
+  buf[0] = 'i';
+  base64_uint16(x, &buf[1]);
+  base64_uint16(y, &buf[4]);
+
+  url = to_png_rgb (w, h, stride, data);
+  len = strlen (url);
+  base64_uint32(len, &buf[7]);
+
+  g_output_stream_write_all (out, buf, 13,
+			     NULL, NULL, NULL);
+
+  g_output_stream_write_all (out, url, len,
+			     NULL, NULL, NULL);
+
+  g_free (url);
+}
+
+
 
 static void
 send_boundary (GOutputStream *out)
@@ -128,6 +322,7 @@ send_draw_ops (GOutputStream *out)
   GOutputStream *cout;
   char *header;
   int i;
+  guint32 pixel[4] = {0xffffff, 0xff0000, 0xff00ff, 0x00ff00};
 
   header =
     "HTTP/1.1 200 OK\r\n"
@@ -154,6 +349,9 @@ send_draw_ops (GOutputStream *out)
 
       send_copyrect (cout, 15, 15, 800, 40, 20, 15);
 
+      send_image_rgb (cout, 30, 30,
+		      2, 2, 2, pixel);
+
       i ++;
 
       flush (cout);
@@ -293,185 +491,12 @@ handler (GThreadedSocketService *service,
   return res;
 }
 
-/* Table of CRCs of all 8-bit messages. */
-static unsigned long crc_table[256];
-
-/* Flag: has the table been computed? Initially false. */
-static int crc_table_computed = 0;
-
-/* Make the table for a fast CRC. */
-static void
-make_crc_table(void)
-{
-  unsigned long c;
-  int n, k;
-
-  for (n = 0; n < 256; n++) {
-    c = (unsigned long) n;
-    for (k = 0; k < 8; k++) {
-      if (c & 1)
-	c = 0xedb88320L ^ (c >> 1);
-      else
-	c = c >> 1;
-    }
-    crc_table[n] = c;
-  }
-  crc_table_computed = 1;
-}
-
-static unsigned long
-update_crc(unsigned long crc, unsigned char *buf, int len)
-{
-  unsigned long c = crc;
-  int n;
-
-  if (!crc_table_computed)
-    make_crc_table();
-  for (n = 0; n < len; n++) {
-    c = crc_table[(c ^ buf[n]) & 0xff] ^ (c >> 8);
-  }
-  return c;
-}
-
-static unsigned long
-crc(unsigned char *buf, int len)
-{
-  return update_crc(0xffffffffL, buf, len) ^ 0xffffffffL;
-}
-
-#define BASE 65521 /* largest prime smaller than 65536 */
-static unsigned long
-update_adler32(unsigned long adler, unsigned char *buf, int len)
-{
-  unsigned long s1 = adler & 0xffff;
-  unsigned long s2 = (adler >> 16) & 0xffff;
-  int n;
-
-  for (n = 0; n < len; n++) {
-    s1 = (s1 + buf[n]) % BASE;
-    s2 = (s2 + s1)     % BASE;
-  }
-  return (s2 << 16) + s1;
-}
-
-char *
-to_png_rgb (int w, int h, int stride, guint32 *data)
-{
-  guchar header[] = {137, 80, 78, 71, 13, 10, 26, 10};
-  guchar ihdr[13+12] = {0, 0, 0, 13, 'I', 'H', 'D', 'R',
-			/* w: */ 0, 0, 0, 0, /* h: */ 0,0,0,0,
-			/* bpp: */ 8, /* color type: */ 2,
-			0, 0, 0};
-  guchar idat_start[8] = { /* len: */0, 0, 0, 0,   'I', 'D', 'A', 'T' };
-  guchar iend[12] = {0, 0, 0, 0, 'I', 'E', 'N', 'D', 0xae, 0x42, 0x60, 0x82};
-  gsize data_size, row_size;
-  char row_header[6];
-  guint8 *png, *p, *p_row, *p_idat;
-  guint32 *row;
-  unsigned long adler;
-  guint32 pixel;
-  gsize png_size;
-  int x, y;
-  char *url, *url_base64;
-  gint state = 0, outlen;
-  gint save = 0;
-
-  *(guint32 *)&ihdr[8] = GUINT32_TO_BE(w);
-  *(guint32 *)&ihdr[12] = GUINT32_TO_BE(h);
-  *(guint32 *)&ihdr[21] = GUINT32_TO_BE(crc(&ihdr[4], 13 + 4));
-
-  row_size = 1 + w * 3;
-  row_header[0] = 0;
-  row_header[1] = row_size & 0xff;
-  row_header[2] = (row_size >> 8) & 0xff;
-  row_header[3] = ~row_header[1];
-  row_header[4] = ~row_header[2];
-  row_header[5] = 0;
-
-  data_size = 2 + (6 + w * 3) * h + 4;
-
-  *(guint32 *)&idat_start[0] = GUINT32_TO_BE(data_size);
-
-  png_size = sizeof(header) + sizeof(ihdr) + 12 + data_size + sizeof(iend);
-  png = g_malloc (png_size);
-
-  p = png;
-  memcpy (p, header, sizeof(header));
-  p += sizeof(header);
-  memcpy (p, ihdr, sizeof(ihdr));
-  p += sizeof(ihdr);
-  memcpy (p, idat_start, sizeof(idat_start));
-  p += sizeof(idat_start);
-
-  /* IDAT data:
-
-     zlib header:  0x78, 0x01 ,
-     h * scanline: row_header[] + width * r,g,b
-     checksum: adler32
-  */
-
-  p_idat = p - 4;
-
-  /* zlib header */
-  *p++ = 0x78;
-  *p++ = 0x01;
-
-  adler = 1;
-
-  /* scanline data */
-  for (y = 0; y < h; y++) {
-    if (y == h - 1)
-      row_header[0] = 1; /* final block */
-    memcpy (p, row_header, sizeof(row_header));
-    p += sizeof(row_header);
-    p_row = p - 1;
-    row = data;
-    data += stride;
-    for (x = 0; x < w; x++) {
-      pixel = *row++;
-      *p++ = (pixel >> 16) & 0xff; /* red */
-      *p++ = (pixel >> 8) & 0xff; /* green */
-      *p++ = (pixel >> 0) & 0xff; /* blue */
-    }
-    adler = update_adler32(adler, p_row, p - p_row);
-  }
-
-  /* adler32 */
-  *(guint32 *)p = GUINT32_TO_BE(adler);
-  p += 4;
-  *(guint32 *)p = GUINT32_TO_BE(crc(p_idat, p - p_idat));
-  p += 4;
-
-  memcpy (p, iend, sizeof(iend));
-  p += sizeof(iend);
-
-  g_assert(p - png == png_size);
-
-  url = g_malloc (strlen("data:image/png;base64,") +
-		  ((png_size / 3 + 1) * 4 + 4) + 1);
-  strcpy (url, "data:image/png;base64,");
-
-  url_base64 = url + strlen("data:image/png;base64,");
-  outlen = g_base64_encode_step (png, png_size, FALSE, url_base64, &state, &save);
-  outlen += g_base64_encode_close (FALSE, url_base64 + outlen, &state, &save);
-  url_base64[outlen] = 0;
-
-  g_free (png);
-
-  return url;
-}
-
 int
 main (int argc, char *argv[])
 {
   GSocketService *service;
   GOptionContext *context;
   GError *error = NULL;
-  guint32 pixel[4] = {0xffffff, 0xff0000, 0xff00ff, 0x00ff00};
-  char *data;
-
-  data = to_png_rgb (2, 2, 2, pixel);
-  g_print ("%s\n", data);
 
   g_type_init ();
   g_thread_init (NULL);