1 files changed, 52 insertions, 19 deletions

diff --git a/fitz/except.c b/fitz/except.c
index 348b950e..4055367d 100644
--- a/fitz/except.c
+++ b/fitz/except.c
@@ -1,3 +1,4 @@
+#include <assert.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -6,44 +7,76 @@
 
 static void do_throw(fz_except_context *ex)
 {
-    if(ex->depth >= 0)
-        longjmp(ex->stack[ex->depth].buffer, 1);
-    else {
-        printf("Uncaught exception: %s\n", ex->except.mess);
-        exit(EXIT_FAILURE);           /* Bale through normal channels */
-    }
+	assert(ex != NULL);
+	if(ex->depth >= 0)
+		longjmp(ex->stack[ex->depth].buffer, 1);
+	else {
+		printf("Uncaught exception: %s\n", ex->except.mess);
+		exit(EXIT_FAILURE); /* Bale through normal channels */
+	}
 }
 
 void fz_throw(fz_context *ctx, char *fmt, ...)
 {
-    va_list args;
+	va_list args;
 
-    va_start(args, fmt);
-    vsprintf(ctx->except->except.mess, fmt, args);
-    va_end(args);
-    do_throw(ctx->except);
+	va_start(args, fmt);
+	vsprintf(ctx->except->except.mess, fmt, args);
+	va_end(args);
+	do_throw(ctx->except);
 }
 
 fz_except *fz_caught(fz_context *ctx)
 {
-    return &ctx->except->except;
+	assert(ctx != NULL);
+	assert(ctx->except != NULL);
+	return &ctx->except->except;
 }
 
 void fz_rethrow(fz_context *ctx)
 {
-    do_throw(ctx->except);
+	assert(ctx != NULL);
+	do_throw(ctx->except);
 }
 
 void fz_except_xxx_push(fz_except_context *ex)
 {
-    if(ex->depth+1 >= MAXDEPTH) {
-        fprintf(stderr, "Exception stack overflow!\n");
-        exit(EXIT_FAILURE);           /* Bale through normal channels */
-    }
-    ex->depth++;
+	assert(ex != NULL);
+	if(ex->depth+1 >= MAXDEPTH) {
+		fprintf(stderr, "Exception stack overflow!\n");
+		exit(EXIT_FAILURE);		   /* Bale through normal channels */
+	}
+	ex->depth++;
 }
 
 void fz_var_xxx(void *e)
 {
-    /* Do nothing */
+	/* Do nothing */
+}
+
+fz_error fz_except_init(fz_context *ctx)
+{
+	fz_except_context *ex;
+
+	assert(ctx != NULL);
+	if (ctx->except != NULL)
+		return fz_okay;
+	ex = fz_malloc_nothrow(ctx, sizeof(fz_except_context));
+	if (ex == NULL)
+		return fz_error_make("Failed to initialise exception context");
+	ex->depth = -1;
+	ctx->except = ex;
+
+	return fz_okay;
+}
+
+void fz_except_fin(fz_context *ctx)
+{
+	assert(ctx != NULL);
+
+	if (ctx->except == NULL)
+		return;
+	assert(ctx->except->depth == -1);
+	free(ctx->except);
+	ctx->except = NULL;
 }