* Add functions that handle a stack-based processing queue.

git-svn-id: file:///srv/caca.zoy.org/var/lib/svn/libpipi/trunk@2692 92316355-f0b4-4df1-b90c-862c8a59935f

pipi/Makefile.am

@@ -16,6 +16,7 @@ libpipi_la_SOURCES = \
 	pipi.c \
 	pipi.h \
 	pipi_internals.h \
+	context.c \
 	pixels.c \
 	codec.c \
 	resize.c \

pipi/context.c

@@ -0,0 +1,95 @@
+/*
+ *  libpipi       Proper image processing implementation library
+ *  Copyright (c) 2004-2008 Sam Hocevar <sam@zoy.org>
+ *                All Rights Reserved
+ *
+ *  $Id$
+ *
+ *  This library is free software. It comes without any warranty, to
+ *  the extent permitted by applicable law. You can redistribute it
+ *  and/or modify it under the terms of the Do What The Fuck You Want
+ *  To Public License, Version 2, as published by Sam Hocevar. See
+ *  http://sam.zoy.org/wtfpl/COPYING for more details.
+ */
+
+/*
+ * context.c: processing stack handling routines
+ */
+
+#include "config.h"
+#include "common.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <string.h>
+
+#include "pipi.h"
+#include "pipi_internals.h"
+
+pipi_context_t *pipi_create_context()
+{
+    pipi_context_t *ret;
+
+    ret = malloc(sizeof(pipi_context_t));
+    memset(ret, 0, sizeof(pipi_context_t));
+
+    return ret;
+}
+
+void pipi_destroy_context(pipi_context_t *ctx)
+{
+    free(ctx);
+}
+
+int pipi_command(pipi_context_t *ctx, char const *cmd, ...)
+{
+    if(!strcmp(cmd, "load"))
+    {
+        char const *file;
+        va_list ap;
+
+        va_start(ap, cmd);
+        file = va_arg(ap, char const *);
+        va_end(ap);
+        ctx->images[ctx->nimages] = pipi_load(file);
+        if(ctx->images[ctx->nimages] == NULL)
+            return -1;
+        ctx->nimages++;
+    }
+    else if(!strcmp(cmd, "save"))
+    {
+        char const *file;
+        va_list ap;
+
+        if(ctx->nimages <= 0)
+            return -1;
+        ctx->nimages--;
+        va_start(ap, cmd);
+        file = va_arg(ap, char const *);
+        va_end(ap);
+        pipi_save(ctx->images[ctx->nimages], file);
+        pipi_free(ctx->images[ctx->nimages]);
+    }
+    else if(!strcmp(cmd, "free"))
+    {
+        if(ctx->nimages <= 0)
+            return -1;
+        ctx->nimages--;
+        pipi_free(ctx->images[ctx->nimages]);
+    }
+    else if(!strcmp(cmd, "dup"))
+    {
+        if(ctx->nimages <= 0)
+            return -1;
+        ctx->images[ctx->nimages] = pipi_copy(ctx->images[ctx->nimages - 1]);
+        ctx->nimages++;
+    }
+    else
+    {
+        return -1;
+    }
+
+    return 0;
+}
+

pipi/pipi.h

@@ -63,6 +63,13 @@ pipi_pixels_t;
 /* pipi_image_t: the main image type */
 typedef struct pipi_image pipi_image_t;
 
+/* pipi_context_t: the processing stack */
+typedef struct pipi_context pipi_context_t;
+
+
+extern pipi_context_t *pipi_create_context(void);
+extern void pipi_destroy_context(pipi_context_t *);
+extern int pipi_command(pipi_context_t *, char const *, ...);
 
 extern pipi_image_t *pipi_load(const char *);
 extern pipi_image_t *pipi_new(int, int);

pipi/pipi_internals.h

@@ -34,6 +34,12 @@ struct pipi_image
     void *codec_priv;
 };
 
+struct pipi_context
+{
+    int nimages;
+    pipi_image_t *images[1024]; /* FIXME: do dynamic allocation */
+};
+
 #ifdef USE_IMLIB2
 pipi_image_t *pipi_load_imlib2(const char *name);
 pipi_image_t *pipi_new_imlib2(int width, int height);