Fl_SVG_Image class: add support for compressed .svgz image files.

git-svn-id: file:///fltk/svn/fltk/branches/branch-1.4@12477 ea41ed52-d2ee-0310-a9c1-e6b18d33e121

1 files changed, 64 insertions, 5 deletions

diff --git a/src/Fl_SVG_Image.cxx b/src/Fl_SVG_Image.cxx
index c30227daa..c5ad1e69f 100644
--- a/src/Fl_SVG_Image.cxx
+++ b/src/Fl_SVG_Image.cxx
@@ -26,6 +26,9 @@
 #include <FL/Fl_Screen_Driver.H>
 #include <stdio.h>
 #include <stdlib.h>
+#if defined(HAVE_LIBZ)
+#include <zlib.h>
+#endif
 
 #if !defined(HAVE_LONG_LONG)
 static double strtoll(const char *str, char **endptr, int base) {
@@ -41,8 +44,8 @@ static double strtoll(const char *str, char **endptr, int base) {
 #include "../nanosvg/altsvgrast.h"
 
 
-/** The constructor loads the SVG image from the given .svg filename or in-memory data.
- \param filename A full path and name pointing to an SVG file, or NULL.
+/** The constructor loads the SVG image from the given .svg/.svgz filename or in-memory data.
+ \param filename A full path and name pointing to a .svg or .svgz file, or NULL.
  \param filedata A pointer to the memory location of the SVG image data.
  This parameter allows to load an SVG image from in-memory data, and is used when \p filename is NULL.
  \note In-memory SVG data is modified by the object constructor and is no longer used after construction.
@@ -73,6 +76,55 @@ float Fl_SVG_Image::svg_scaling_(int W, int H) {
   return (f1 < f2) ? f1 : f2;
 }
 
+/** Opens for reading a potentially gzip'ed file identified by a UTF-8 encoded filename. */
+void* Fl_SVG_Image::gzopen(const char *fname) {
+#if defined(HAVE_LIBZ)
+#  ifdef _WIN32
+  unsigned wl = fl_utf8towc(fname, strlen(fname), NULL, 0) + 1;
+  wchar_t *wc = new wchar_t[wl];
+  fl_utf8towc(fname, strlen(fname), wc, wl);
+  gzFile gzf = gzopen_w(wc, "r");
+  delete[] wc;
+  return gzf;
+#  else
+  int fd = fl_open(fname, 0);
+  if (fd < 0) return NULL;
+  return gzdopen(fd, "r");
+#  endif
+#else
+  return NULL;
+#endif // HAVE_LIBZ
+}
+
+#if defined(HAVE_LIBZ)
+
+static char *svg_inflate(const char *fname) {
+  struct stat b;
+  fl_stat(fname, &b);
+  long size = b.st_size;
+  gzFile gzf = (gzFile)Fl_SVG_Image::gzopen(fname);
+  int l;
+  bool direct = gzdirect(gzf);
+  long out_size = direct ? size + 1 : 3*size + 1;
+  char *out = (char*)malloc(out_size);
+  char *p = out;
+  do {
+    if ((!direct) && p + size > out + out_size) {
+      out_size += size;
+      char *tmp = (char*)realloc(out, out_size + 1);
+      p = tmp + (p - out);
+      out = tmp;
+    }
+    l = gzread(gzf, p, size);
+    if (l > 0) {
+      p += l; *p = 0;
+    }
+  } while ((!direct) && l >0);
+  gzclose(gzf);
+  if (!direct) out = (char*)realloc(out, (p-out)+1);
+  return out;
+}
+#endif
 
 void Fl_SVG_Image::init_(const char *filename, char *filedata, Fl_SVG_Image *copy_source) {
   if (copy_source) {
@@ -88,22 +140,29 @@ void Fl_SVG_Image::init_(const char *filename, char *filedata, Fl_SVG_Image *cop
   average_weight_ = 1;
   proportional = true;
   if (filename) {
+#if defined(HAVE_LIBZ)
+    filedata = svg_inflate(filename);
+#else
     filedata = NULL;
     FILE *fp = fl_fopen(filename, "rb");
     if (fp) {
       fseek(fp, 0, SEEK_END);
-      size_t size = ftell(fp);
+      long size = ftell(fp);
       fseek(fp, 0, SEEK_SET);
       filedata = (char*)malloc(size+1);
       if (filedata) {
-        if (fread(filedata, 1, size, fp) == size) filedata[size] = '\0';
+        if (fread(filedata, 1, size, fp) == size) {
+          filedata[size] = '\0';
+        }
         else {
           free(filedata);
           filedata = NULL;
         }
       }
       fclose(fp);
-    } else ld(ERR_FILE_ACCESS);
+    }
+#endif // HAVE_LIBZ
+    if (!filedata) ld(ERR_FILE_ACCESS);
   }
   if (filedata) {
     counted_svg_image_->svg_image = nsvgParse(filedata, "px", 96);