From aef381e3ac79970a4167fd9f0d5d681e4203ef5e Mon Sep 17 00:00:00 2001
From: Cyril Hrubis <metan@ucw.cz>
Date: Sat, 2 Jun 2012 20:14:04 +0200
Subject: [PATCH] loaders: Add generic function to load Meta Data.

---
 demos/c_simple/Makefile                            |  2 +-
 .../c_simple/{meta_data_png.c => meta_data_dump.c} |  6 +--
 include/loaders/GP_Loaders.h                       |  5 +++
 libs/loaders/GP_Loaders.c                          | 44 ++++++++++++++++++++++
 4 files changed, 53 insertions(+), 4 deletions(-)
 rename demos/c_simple/{meta_data_png.c => meta_data_dump.c} (94%)

diff --git a/demos/c_simple/Makefile b/demos/c_simple/Makefile
index c03f3741..22efd37c 100644
--- a/demos/c_simple/Makefile
+++ b/demos/c_simple/Makefile
@@ -6,7 +6,7 @@ INCLUDE=
 LDLIBS+=-lGP -lGP_backends -lSDL -L$(TOPDIR)/build/
 
 APPS=backend_example loaders_example loaders filters_symmetry gfx_koch\
-     virtual_backend_example meta_data meta_data_png
+     virtual_backend_example meta_data meta_data_dump
 
 include $(TOPDIR)/pre.mk
 include $(TOPDIR)/app.mk
diff --git a/demos/c_simple/meta_data_png.c b/demos/c_simple/meta_data_dump.c
similarity index 94%
rename from demos/c_simple/meta_data_png.c
rename to demos/c_simple/meta_data_dump.c
index 9f6543b6..d9aacfb3 100644
--- a/demos/c_simple/meta_data_png.c
+++ b/demos/c_simple/meta_data_dump.c
@@ -22,7 +22,7 @@
 
  /*
 
-   Read png meta-data and print them into stdout.
+   Read image meta-data and print them into stdout.
 
   */
 
@@ -37,7 +37,7 @@
 
 int main(int argc, char *argv[])
 {
-	GP_MetaData *data = GP_MetaDataCreate(20);
+	GP_MetaData *data = GP_MetaDataCreate(80);
 	int i;
 
 	if (argc < 2) {
@@ -53,7 +53,7 @@ int main(int argc, char *argv[])
 		
 		GP_MetaDataClear(data);
 		
-		if (GP_LoadPNGMetaData(argv[i], data)) {
+		if (GP_LoadMetaData(argv[i], data)) {
 			fprintf(stderr, "Failed to read '%s' meta-data: %s\n",
 			        argv[1], strerror(errno));
 		} else {
diff --git a/include/loaders/GP_Loaders.h b/include/loaders/GP_Loaders.h
index d374f996..c7aab954 100644
--- a/include/loaders/GP_Loaders.h
+++ b/include/loaders/GP_Loaders.h
@@ -54,6 +54,11 @@
 GP_Context *GP_LoadImage(const char *src_path, GP_ProgressCallback *callback);
 
 /*
+ * Loads image Meta Data (if possible).
+ */
+int GP_LoadMetaData(const char *src_path, GP_MetaData *data);
+
+/*
  * Simple saving function, the image format is matched by file extension.
  *
  * Retruns zero on succes.
diff --git a/libs/loaders/GP_Loaders.c b/libs/loaders/GP_Loaders.c
index a6349bcb..f298983e 100644
--- a/libs/loaders/GP_Loaders.c
+++ b/libs/loaders/GP_Loaders.c
@@ -148,6 +148,50 @@ skip_filename_check:
 	return NULL;
 }
 
+int GP_LoadMetaData(const char *src_path, GP_MetaData *data)
+{
+	int len;
+	
+	len = strlen(src_path);
+
+	if (len < 3) {
+		errno = ENOSYS;
+		return 1;
+	}
+
+	switch (src_path[len - 1]) {
+	/* PNG, JPG, JPEG */
+	case 'g':
+	case 'G':
+		switch (src_path[len - 2]) {
+		case 'n':
+		case 'N':
+			if (src_path[len - 3] == 'p' ||
+			    src_path[len - 3] == 'P')
+				return GP_LoadPNGMetaData(src_path, data); 
+		break;
+		case 'p':
+		case 'P':
+			if (src_path[len - 3] == 'j' ||
+			    src_path[len - 3] == 'J')
+				return GP_LoadJPGMetaData(src_path, data); 
+		break;
+		case 'e':
+		case 'E':
+			if ((src_path[len - 3] == 'p' ||
+			     src_path[len - 3] == 'P') &&
+			    (src_path[len - 4] == 'j' ||
+			     src_path[len - 4] == 'J'))
+				return GP_LoadJPGMetaData(src_path, data); 
+		break;
+		}
+	break;
+	}
+
+	errno = ENOSYS;
+	return 1;
+}
+
 int GP_SaveImage(const GP_Context *src, const char *dst_path,
                  GP_ProgressCallback *callback)
 {
-- 
2.11.4.GIT