Synchronized bundled GD library with GD 2.0.17

 . GD is now thread-safe thanks to wrappers around freetype library
 . Significant optimization to png writing code.
 . Miscellaneous fixes.
Fixed memory leak inside php_imagettftext_common()
Make ext/gd compile with GD 2.0.17+ (gdFreeFontCache() is not avaliable)

12 files changed, 190 insertions, 83 deletions

diff --git a/ext/gd/config.m4 b/ext/gd/config.m4
index aacb084e13..05e406cb0b 100644
--- a/ext/gd/config.m4
+++ b/ext/gd/config.m4
@@ -258,6 +258,7 @@ AC_DEFUN(PHP_GD_CHECK_VERSION,[
   PHP_CHECK_LIBRARY(gd, gdImageColorResolve,    [AC_DEFINE(HAVE_GDIMAGECOLORRESOLVE, 1, [ ])], [], [ -L$GD_LIB $GD_SHARED_LIBADD ])
   PHP_CHECK_LIBRARY(gd, gdImageGifCtx,          [AC_DEFINE(HAVE_GD_GIF_CTX,          1, [ ])], [], [ -L$GD_LIB $GD_SHARED_LIBADD ])
   PHP_CHECK_LIBRARY(gd, gdCacheCreate,          [AC_DEFINE(HAVE_GD_CACHE_CREATE,     1, [ ])], [], [ -L$GD_LIB $GD_SHARED_LIBADD ])
+  PHP_CHECK_LIBRARY(gd, gdFontCacheShutdown,    [AC_DEFINE(HAVE_GD_THREAD_SAFE,      1, [ ])], [], [ -L$GD_LIB $GD_SHARED_LIBADD ])
 ])
 
 dnl
diff --git a/ext/gd/gd.c b/ext/gd/gd.c
index 08c208db40..a13b211923 100644
--- a/ext/gd/gd.c
+++ b/ext/gd/gd.c
@@ -442,14 +442,18 @@ PHP_MINIT_FUNCTION(gd)
 #if HAVE_LIBGD20 && HAVE_GD_STRINGFT
 PHP_RSHUTDOWN_FUNCTION(gd)
 {
+#if defined(HAVE_GD_THREAD_SAFE) || defined(HAVE_GD_BUNDLED)
+	gdFontCacheShutdown();
+#else 
 	gdFreeFontCache();
+#endif
 	return SUCCESS;
 }
 #endif
 /* }}} */
 
 #if HAVE_GD_BUNDLED
-#define PHP_GD_VERSION_STRING "bundled (2.0.15 compatible)"
+#define PHP_GD_VERSION_STRING "bundled (2.0.17 compatible)"
 #elif HAVE_LIBGD20
 #define PHP_GD_VERSION_STRING "2.0 or higher"
 #elif HAVE_GDIMAGECOLORRESOLVE
@@ -3077,7 +3081,7 @@ static void php_imagettftext_common(INTERNAL_FUNCTION_PARAMETERS, int mode, int
 	char *error = NULL;
 	int argc;
 #if HAVE_GD_STRINGFTEX
-	gdFTStringExtra strex;
+	gdFTStringExtra strex = {0};
 #endif
 
 #if !HAVE_GD_STRINGFTEX
@@ -3120,7 +3124,6 @@ static void php_imagettftext_common(INTERNAL_FUNCTION_PARAMETERS, int mode, int
 			HashPosition pos;
 
 			convert_to_array_ex(EXT);
-			memset(&strex, 0, sizeof(strex));
 
 			/* walk the assoc array */
 			zend_hash_internal_pointer_reset_ex(HASH_OF(*EXT), &pos);
@@ -3156,8 +3159,11 @@ static void php_imagettftext_common(INTERNAL_FUNCTION_PARAMETERS, int mode, int
 	l = strlen(str);
 
 #ifdef VIRTUAL_DIR
-	if (virtual_filepath(Z_STRVAL_PP(FONTNAME), (char **) &fontname TSRMLS_CC)) {
-		fontname = (unsigned char *) Z_STRVAL_PP(FONTNAME);
+	{
+		char tmp_font_path[MAXPATHLEN];
+		if (VCWD_REALPATH(Z_STRVAL_PP(FONTNAME), tmp_font_path)) {
+			fontname = (unsigned char *) Z_STRVAL_PP(FONTNAME);
+		}
 	}
 #else
 	fontname = (unsigned char *) Z_STRVAL_PP(FONTNAME);
diff --git a/ext/gd/libgd/gd.c b/ext/gd/libgd/gd.c
index 9b9413320c..4fb3c4f0c8 100644
--- a/ext/gd/libgd/gd.c
+++ b/ext/gd/libgd/gd.c
@@ -94,7 +94,7 @@ static int gdFullAlphaBlend(int dst, int src);
 static int gdLayerOverlay(int dst, int src);
 static int gdAlphaBlendColor(int b1, int b2, int a1, int a2);
 static int gdAlphaOverlayColor(int src, int dst, int max);
-static int gdImageGetTrueColorPixel(gdImagePtr im, int x, int y);
+int gdImageGetTrueColorPixel(gdImagePtr im, int x, int y);
 
 void php_gd_error_ex(int type, const char *format, ...) 
 {
@@ -751,7 +751,7 @@ void gdImageSetPixel (gdImagePtr im, int x, int y, int color)
 	}
 }
 
-static int gdImageGetTrueColorPixel (gdImagePtr im, int x, int y)
+int gdImageGetTrueColorPixel (gdImagePtr im, int x, int y)
 {
 	int p = gdImageGetPixel(im, x, y);
 
@@ -2255,20 +2255,12 @@ void gdImageCopyResized (gdImagePtr dst, gdImagePtr src, int dstX, int dstY, int
 	sty = (int *) gdMalloc (sizeof (int) * srcH);
 	accum = 0;
 	
+	/* Fixed by Mao Morimoto 2.0.16 */
 	for (i = 0; (i < srcW); i++) {
-		int got;
-		accum += (double) dstW / (double) srcW;
-		got = (int) floor (accum);
-		stx[i] = got;
-		accum -= got;
+		stx[i] = dstW * (i+1) / srcW - dstW * i / srcW ;
 	}
-	accum = 0;
 	for (i = 0; (i < srcH); i++) {
-		int got;
-		accum += (double) dstH / (double) srcH;
-		got = (int) floor (accum);
-		sty[i] = got;
-		accum -= got;
+		sty[i] = dstH * (i+1) / srcH - dstH * i / srcH ;
 	}
 	for (i = 0; (i < gdMaxColors); i++) {
 		colorMap[i] = (-1);
@@ -3019,6 +3011,15 @@ void gdImageFilledPolygon (gdImagePtr im, gdPointPtr p, int n, int c)
 			maxy = p[i].y;
 		}
 	}
+
+	/* 2.0.16: Optimization by Ilia Chipitsine -- don't waste time offscreen */
+	if (miny < 0) {
+		miny = 0;
+	}
+	if (maxy >= gdImageSY(im)) {
+		maxy = gdImageSY(im) - 1;
+	} 
+
 	/* Fix in 1.3: count a vertex only once */
 	for (y = miny; y <= maxy; y++) {
 		/*1.4           int interLast = 0; */
diff --git a/ext/gd/libgd/gd.h b/ext/gd/libgd/gd.h
index 4742fd5ab9..20f5561378 100644
--- a/ext/gd/libgd/gd.h
+++ b/ext/gd/libgd/gd.h
@@ -295,8 +295,16 @@ void gdImageStringUp(gdImagePtr im, gdFontPtr f, int x, int y, unsigned char *s,
 void gdImageString16(gdImagePtr im, gdFontPtr f, int x, int y, unsigned short *s, int color);
 void gdImageStringUp16(gdImagePtr im, gdFontPtr f, int x, int y, unsigned short *s, int color);
 
-/* clean up after using fonts in gdImageStringFT() */
-void gdFreeFontCache();
+/* 2.0.16: for thread-safe use of gdImageStringFT and friends,
+ * call this before allowing any thread to call gdImageStringFT. 
+ * Otherwise it is invoked by the first thread to invoke
+ * gdImageStringFT, with a very small but real risk of a race condition. 
+ * Return 0 on success, nonzero on failure to initialize freetype.
+ */
+int gdFontCacheSetup(void);
+
+/* Optional: clean up after application is done using fonts in gdImageStringFT(). */
+void gdFontCacheShutdown(void);
 
 /* Calls gdImageStringFT. Provided for backwards compatibility only. */
 char *gdImageStringTTF(gdImage *im, int *brect, int fg, char *fontlist,
diff --git a/ext/gd/libgd/gd_gd2.c b/ext/gd/libgd/gd_gd2.c
index 5034afec60..2fdbdd44d5 100644
--- a/ext/gd/libgd/gd_gd2.c
+++ b/ext/gd/libgd/gd_gd2.c
@@ -539,7 +539,7 @@ gdImagePtr gdImageCreateFromGd2PartCtx (gdIOCtx * in, int srcx, int srcy, int w,
 							}
 						} else {
 							ch = gdGetC(in);
-							if (ch == EOF) {
+							if ((int)ch == EOF) {
 								ch = 0;
 							}
 						}
diff --git a/ext/gd/libgd/gd_io.c b/ext/gd/libgd/gd_io.c
index 9dbd1862a2..6a39e16eb1 100644
--- a/ext/gd/libgd/gd_io.c
+++ b/ext/gd/libgd/gd_io.c
@@ -3,7 +3,7 @@
 /*
    * io.c
    *
-   * Implements the imple I/O 'helper' routines.
+   * Implements the simple I/O 'helper' routines.
    *
    * Not really essential, but these routines were used extensively in GD,
    * so they were moved here. They also make IOCtx calls look better...
diff --git a/ext/gd/libgd/gd_io_file.c b/ext/gd/libgd/gd_io_file.c
index 4544489890..8318a45969 100644
--- a/ext/gd/libgd/gd_io_file.c
+++ b/ext/gd/libgd/gd_io_file.c
@@ -34,8 +34,6 @@ typedef struct fileIOCtx
 	FILE *f;
 } fileIOCtx;
 
-struct fileIOCtx *fileIOCtxPtr;
-
 gdIOCtx *newFileCtx (FILE * f);
 
 static int fileGetbuf (gdIOCtx *, void *, int);
diff --git a/ext/gd/libgd/gd_jpeg.c b/ext/gd/libgd/gd_jpeg.c
index a2b8b62d90..ce5d84a0fb 100644
--- a/ext/gd/libgd/gd_jpeg.c
+++ b/ext/gd/libgd/gd_jpeg.c
@@ -328,6 +328,11 @@ gdImagePtr gdImageCreateFromJpegCtx (gdIOCtx * infile)
 		php_gd_error("gd-jpeg: warning: jpeg_finish_decompress reports suspended data source");
 	}
 
+	/* Thanks to Truxton Fulton */
+	if (cinfo.err->num_warnings > 0) {
+		goto error;
+	}
+
 	jpeg_destroy_decompress (&cinfo);
 	gdFree (row);
 
diff --git a/ext/gd/libgd/gd_png.c b/ext/gd/libgd/gd_png.c
index 35c16e7af9..dbb139fc61 100644
--- a/ext/gd/libgd/gd_png.c
+++ b/ext/gd/libgd/gd_png.c
@@ -622,28 +622,39 @@ void gdImagePngCtxEx (gdImagePtr im, gdIOCtx * outfile, int level)
 	 */
 
 	if (im->trueColor) {
+		/* performance optimizations by Phong Tran */
 		int channels = im->saveAlphaFlag ? 4 : 3;
 		/* Our little 7-bit alpha channel trick costs us a bit here. */
 		png_bytep *row_pointers;
+		unsigned char* pOutputRow;
+		int **ptpixels = im->tpixels;
+		int *pThisRow;
+		unsigned char a;
+		int thisPixel;
+		png_bytep *prow_pointers;
+		int saveAlphaFlag = im->saveAlphaFlag;
+
 		row_pointers = safe_emalloc(sizeof(png_bytep), height, 0);
+		prow_pointers = row_pointers;
 		for (j = 0; j < height; ++j) {
-			int bo = 0;
-			row_pointers[j] = (png_bytep) safe_emalloc(width, channels, 0);
+			*prow_pointers = (png_bytep) safe_emalloc(width, channels, 0);
+			pOutputRow = *prow_pointers++;
+			pThisRow = *ptpixels++;
 			for (i = 0; i < width; ++i) {
-				unsigned char a;
-				row_pointers[j][bo++] = gdTrueColorGetRed(im->tpixels[j][i]);
-				row_pointers[j][bo++] = gdTrueColorGetGreen(im->tpixels[j][i]);
-				row_pointers[j][bo++] = gdTrueColorGetBlue(im->tpixels[j][i]);
-				if (im->saveAlphaFlag) {
+				thisPixel = *pThisRow++;
+				*pOutputRow++ = gdTrueColorGetRed(thisPixel);
+				*pOutputRow++ = gdTrueColorGetGreen(thisPixel);
+				*pOutputRow++ = gdTrueColorGetBlue(thisPixel);
+				if (saveAlphaFlag) {
 					/* convert the 7-bit alpha channel to an 8-bit alpha channel.
 					 * We do a little bit-flipping magic, repeating the MSB
 					 * as the LSB, to ensure that 0 maps to 0 and
 					 * 127 maps to 255. We also have to invert to match
 					 * PNG's convention in which 255 is opaque.
 					 */
-					a = gdTrueColorGetAlpha(im->tpixels[j][i]);
+					a = gdTrueColorGetAlpha(thisPixel);
 					/* Andrew Hull: >> 6, not >> 7! (gd 2.0.5) */ 
-					row_pointers[j][bo++] = 255 - ((a << 1) + (a >> 6));
+					*pOutputRow++ = 255 - ((a << 1) + (a >> 6));
 				}
 			}
 		}
diff --git a/ext/gd/libgd/gd_topal.c b/ext/gd/libgd/gd_topal.c
index 77fb4139b2..b60a055aef 100644
--- a/ext/gd/libgd/gd_topal.c
+++ b/ext/gd/libgd/gd_topal.c
@@ -703,7 +703,7 @@ LOCAL (void)
 	histptr histp;
 	int c0, c1, c2;
 	int c0min, c0max, c1min, c1max, c2min, c2max;
-	long count;
+	long count = 0;
 	long total = 0;
 	long c0total = 0;
 	long c1total = 0;
@@ -735,9 +735,16 @@ LOCAL (void)
 	cinfo->colormap[1][icolor] = (JSAMPLE) ((c1total + (total >> 1)) / total);
 	cinfo->colormap[2][icolor] = (JSAMPLE) ((c2total + (total >> 1)) / total);
 #else
-	im->red[icolor] = (int) ((c0total + (total >> 1)) / total);
-	im->green[icolor] = (int) ((c1total + (total >> 1)) / total);
-	im->blue[icolor] = (int) ((c2total + (total >> 1)) / total);
+	/* 2.0.16: Paul den Dulk found an occasion where total can be 0 */
+	if (count) {
+		im->red[icolor] = (int) ((c0total + (total >> 1)) / total);
+		im->green[icolor] = (int) ((c1total + (total >> 1)) / total);
+		im->blue[icolor] = (int) ((c2total + (total >> 1)) / total);
+	} else {
+		im->red[icolor] = 255;
+		im->green[icolor] = 255;
+		im->blue[icolor] = 255;
+	}
 #endif
 }
 
diff --git a/ext/gd/libgd/gdft.c b/ext/gd/libgd/gdft.c
index b94a56a3cf..4d34d5ec9f 100644
--- a/ext/gd/libgd/gdft.c
+++ b/ext/gd/libgd/gdft.c
@@ -92,8 +92,12 @@ gdImageStringFT (gdImage * im, int *brect, int fg, char *fontlist,
  * if building this version of gd separate from graphviz.
  */
 #ifndef DEFAULT_FONTPATH
+#if defined(__APPLE__) || (defined(__MWERKS__) && defined(macintosh))
+#define DEFAULT_FONTPATH "/usr/share/fonts/truetype:/System/Library/Fonts:/Library/Fonts"
+#else
 #define DEFAULT_FONTPATH "/usr/share/fonts/truetype"
 #endif
+#endif
 #ifndef PATHSEPARATOR
 #define PATHSEPARATOR ":"
 #endif
@@ -408,26 +412,18 @@ static void *fontFetch (char **error, void *key)
 				}
 			}
 
-			snprintf(fullname, sizeof(fullname) - 1, "%s/%s", dir, name);
-			if (access(fullname, R_OK) == 0) {
-				font_found++;
-				break;
-			}
-			snprintf(fullname, sizeof(fullname) - 1, "%s/%s.ttf", dir, name);
-			if (access(fullname, R_OK) == 0) {
-				font_found++;
-				break;
-			}
-			snprintf(fullname, sizeof(fullname) - 1, "%s/%s.pfa", dir, name);
-			if (access(fullname, R_OK) == 0) {
-				font_found++;
-				break;
-			}
-			snprintf(fullname, sizeof(fullname) - 1, "%s/%s.pfb", dir, name);
-			if (access(fullname, R_OK) == 0) {
-				font_found++;
-				break;
-			}
+#define GD_CHECK_FONT_PATH(ext)	\
+	snprintf(fullname, sizeof(fullname) - 1, "%s/%s%s", dir, name, ext);	\
+	if (access(fullname, R_OK) == 0) {	\
+		font_found++;	\
+		break;	\
+	}	\
+
+			GD_CHECK_FONT_PATH("");
+			GD_CHECK_FONT_PATH(".ttf");
+			GD_CHECK_FONT_PATH(".pfa");
+			GD_CHECK_FONT_PATH(".pfb");
+			GD_CHECK_FONT_PATH(".dfont");
 		}
 		gdFree(path);
 		path = NULL;
@@ -458,6 +454,16 @@ static void *fontFetch (char **error, void *key)
 	}
 
 	/* FIXME - This mapping stuff is imcomplete - where is the spec? */
+	/* EAM   - It's worse than that. It's pointless to match character encodings here.
+	 *         As currently written, the stored a->face->charmap only matches one of
+	 *         the actual charmaps and we cannot know at this stage if it is the right
+	 *         one. We should just skip all this stuff, and check in gdImageStringFTEx
+	 *         if some particular charmap is preferred and if so whether it is held in
+	 *         one of the a->face->charmaps[0..num_charmaps].
+	 *         And why is it so bad not to find any recognized charmap?  The user may
+	 *         still know what mapping to use, even if we do not.  In that case we can
+	 *         just use the map in a->face->charmaps[num_charmaps] and be done with it.
+	 */
 
 	a->have_char_map_unicode = 0;
 	a->have_char_map_big5 = 0;
@@ -467,6 +473,20 @@ static void *fontFetch (char **error, void *key)
 		charmap = a->face->charmaps[n];
 		platform = charmap->platform_id;
 		encoding = charmap->encoding_id;
+
+/* EAM DEBUG - Newer versions of libfree2 make it easier by defining encodings */
+#ifdef FT_ENCODING_MS_SYMBOL
+	if (charmap->encoding == FT_ENCODING_MS_SYMBOL
+		|| charmap->encoding == FT_ENCODING_ADOBE_CUSTOM
+		|| charmap->encoding == FT_ENCODING_ADOBE_STANDARD) {
+		a->have_char_map_unicode = 1;
+		found = charmap;
+		a->face->charmap = charmap;
+		return (void *)a;
+	}
+#endif /* FT_ENCODING_MS_SYMBOL */
+/* EAM DEBUG */
+
 		if ((platform == 3 && encoding == 1)		/* Windows Unicode */
 			|| (platform == 3 && encoding == 0)	/* Windows Symbol */
 			|| (platform == 2 && encoding == 1)	/* ISO Unicode */
@@ -511,16 +531,12 @@ static void fontRelease (void *element)
 /********************************************************************/
 /* tweencolor cache functions                                            */
 
-static int
-tweenColorTest (void *element, void *key)
+static int tweenColorTest (void *element, void *key)
 {
-  tweencolor_t *a = (tweencolor_t *) element;
-  tweencolorkey_t *b = (tweencolorkey_t *) key;
+	tweencolor_t *a = (tweencolor_t *) element;
+	tweencolorkey_t *b = (tweencolorkey_t *) key;
 
-  return (a->pixel == b->pixel
-	  && a->bgcolor == b->bgcolor
-	  && a->fgcolor == b->fgcolor
-	  && a->im == b->im);
+	return (a->pixel == b->pixel && a->bgcolor == b->bgcolor && a->fgcolor == b->fgcolor && a->im == b->im);
 }
 
 /*
@@ -610,7 +626,8 @@ gdft_draw_bitmap (gdCache_head_t *tc_cache, gdImage * im, int fg, FT_Bitmap bitm
         pcr = pc;
         y = pen_y + row;
         /* clip if out of bounds */
-        if (y >= im->sy || y < 0)
+        /* 2.0.16: clipping rectangle, not image bounds */		
+	if ((y > im->cy2) || (y < im->cy1))
 	  continue;
       for (col = 0; col < bitmap.width; col++, pc++)
 	{
@@ -645,7 +662,8 @@ gdft_draw_bitmap (gdCache_head_t *tc_cache, gdImage * im, int fg, FT_Bitmap bitm
           level = gdAlphaMax - level;  
           x = pen_x + col;
 	      /* clip if out of bounds */
-	      if (x >= im->sx || x < 0)
+	      /* 2.0.16: clip to clipping rectangle, Matt McNabb */
+		if ((x > im->cx2) || (x < im->cx1))
 		continue;
 	      /* get pixel location in gd buffer */
 	    tpixel = &im->tpixels[y][x];
@@ -745,30 +763,47 @@ gdroundupdown (FT_F26Dot6 v1, int updown)
 extern int any2eucjp (char *, char *, unsigned int);
 
 /* Persistent font cache until explicitly cleared */
-/*     Fonts can be used across multiple images */
+/* Fonts can be used across multiple images */
+
+/* 2.0.16: thread safety (the font cache is shared) */
+gdMutexDeclare(gdFontCacheMutex);
 static gdCache_head_t *fontCache = NULL;
 static FT_Library library;
 
-void
-gdFreeFontCache()
+void gdFontCacheShutdown()
 {
-  if (fontCache)
-    {
-      gdCacheDelete(fontCache);
-	  fontCache = NULL;
-      FT_Done_FreeType(library);
-    }
+	if (fontCache) {
+		gdMutexShutdown(gdFontCacheMutex);
+		gdCacheDelete(fontCache);
+		fontCache = NULL;
+		FT_Done_FreeType(library);
+	}
+}
+
+int gdFontCacheSetup(void)
+{
+	if (fontCache) {
+		/* Already set up */
+		return 0;
+	}
+	gdMutexSetup(gdFontCacheMutex);
+	if (FT_Init_FreeType(&library)) {
+		gdMutexShutdown(gdFontCacheMutex);
+		return -1;
+	}
+	fontCache = gdCacheCreate (FONTCACHESIZE, fontTest, fontFetch, fontRelease);
+	return 0;
 }
 
+
 /********************************************************************/
 /* gdImageStringFT -  render a utf8 string onto a gd image          */
 
 char *
-gdImageStringFT (gdImage * im, int *brect, int fg, char *fontlist,
+gdImageStringFT (gdImage * im, int *brect, int fg, char *fontlist, 
 		 double ptsize, double angle, int x, int y, char *string)
 {
-	return gdImageStringFTEx(im, brect, fg, fontlist,
-		ptsize, angle, x, y, string, 0);
+	return gdImageStringFTEx(im, brect, fg, fontlist, ptsize, angle, x, y, string, 0);
 }
 
 char *
@@ -815,20 +850,21 @@ gdImageStringFTEx (gdImage * im, int *brect, int fg, char *fontlist, double ptsi
 	/***** initialize font library and font cache on first call ******/
 
 	if (!fontCache) {
-		if (FT_Init_FreeType (&library)) {
-			gdCacheDelete( tc_cache );
+		if (gdFontCacheSetup() != 0) {
+			gdCacheDelete(tc_cache);
 			return "Failure to initialize font library";
 		}
-		fontCache = gdCacheCreate(FONTCACHESIZE, fontTest, fontFetch, fontRelease);
 	}
 	/*****/
-
+	
+	gdMutexLock(gdFontCacheMutex);
 	/* get the font (via font cache) */
 	fontkey.fontlist = fontlist;
 	fontkey.library = &library;
 	font = (font_t *) gdCacheGet (fontCache, &fontkey);
 	if (!font) {
 		gdCacheDelete(tc_cache);
+		gdMutexUnlock(gdFontCacheMutex);
 		return fontCache->error;
 	}
 	face = font->face;		/* shortcut */
@@ -836,6 +872,7 @@ gdImageStringFTEx (gdImage * im, int *brect, int fg, char *fontlist, double ptsi
 
 	if (FT_Set_Char_Size (face, 0, (FT_F26Dot6) (ptsize * 64), GD_RESOLUTION, GD_RESOLUTION)) {
 		gdCacheDelete(tc_cache);
+		gdMutexUnlock(gdFontCacheMutex);
 		return "Could not set character size";
 	}
 
@@ -887,6 +924,7 @@ gdImageStringFTEx (gdImage * im, int *brect, int fg, char *fontlist, double ptsi
 	}
 	if (!mfound) {
 		/* No character set found! */
+		gdMutexUnlock(gdFontCacheMutex);
 		return "No character set found";
 	}
 
@@ -928,6 +966,21 @@ gdImageStringFTEx (gdImage * im, int *brect, int fg, char *fontlist, double ptsi
 			  next++;
 			  continue;
 		}
+
+/* EAM DEBUG */
+#ifdef FT_ENCODING_MS_SYMBOL
+		if (font->face->charmap->encoding == FT_ENCODING_MS_SYMBOL) {
+			/* I do not know the significance of the constant 0xf000.
+			 * It was determined by inspection of the character codes
+			 * stored in Microsoft font symbol.
+			 */
+			len = gdTcl_UtfToUniChar (next, &ch);
+			ch |= 0xf000;
+			next += len;
+		} else
+#endif /* FT_ENCODING_MS_SYMBOL */
+/* EAM DEBUG */
+
 		switch (m) {
 			case gdFTEX_Unicode:
 				if (font->have_char_map_unicode) {
@@ -1005,6 +1058,7 @@ gdImageStringFTEx (gdImage * im, int *brect, int fg, char *fontlist, double ptsi
 				gdFree(tmpstr);
 			}
 			gdCacheDelete(tc_cache);
+			gdMutexUnlock(gdFontCacheMutex);
 			return "Problem loading glyph";
 		}
 
@@ -1047,6 +1101,7 @@ gdImageStringFTEx (gdImage * im, int *brect, int fg, char *fontlist, double ptsi
 					gdFree(tmpstr);
 				}
 				gdCacheDelete(tc_cache);
+				gdMutexUnlock(gdFontCacheMutex);
 				return "Problem rendering glyph";
 			}
 
@@ -1097,6 +1152,7 @@ gdImageStringFTEx (gdImage * im, int *brect, int fg, char *fontlist, double ptsi
 		gdFree(tmpstr);
 	}
 	gdCacheDelete(tc_cache);
+	gdMutexUnlock(gdFontCacheMutex);
 	return (char *) NULL;
 }
 
diff --git a/ext/gd/libgd/gdhelpers.h b/ext/gd/libgd/gdhelpers.h
index 2544e88060..33223318f1 100644
--- a/ext/gd/libgd/gdhelpers.h
+++ b/ext/gd/libgd/gdhelpers.h
@@ -21,5 +21,19 @@ extern char *gd_strtok_r(char *s, char *sep, char **state);
 #define gdPFree(ptr)		pefree(ptr, 1)
 #define gdPEstrdup(ptr)		pestrdup(ptr, 1)
 
+#ifdef ZTS
+#define gdMutexDeclare(x) MUTEX_T x
+#define gdMutexSetup(x) x = tsrm_mutex_alloc()
+#define gdMutexShutdown(x) tsrm_mutex_free(x)
+#define gdMutexLock(x) tsrm_mutex_lock(x)
+#define gdMutexUnlock(x) tsrm_mutex_unlock(x)
+#else
+#define gdMutexDeclare(x)
+#define gdMutexSetup(x)
+#define gdMutexShutdown(x)
+#define gdMutexLock(x)
+#define gdMutexUnlock(x)
+#endif
+
 #endif /* GDHELPERS_H */