Add user context field.

This may help the MuPDF JNI code, so it's likely to be useful for
other users too.

2 files changed, 35 insertions, 0 deletions

diff --git a/include/mupdf/fitz/context.h b/include/mupdf/fitz/context.h
index 67b16b00..0dce749c 100644
--- a/include/mupdf/fitz/context.h
+++ b/include/mupdf/fitz/context.h
@@ -101,6 +101,7 @@ void fz_flush_warnings(fz_context *ctx);
 
 struct fz_context_s
 {
+	void *user;
 	fz_alloc_context *alloc;
 	fz_locks_context *locks;
 	fz_id_context *id;
@@ -190,6 +191,24 @@ fz_context *fz_clone_context(fz_context *ctx);
 void fz_drop_context(fz_context *ctx);
 
 /*
+	fz_set_user_context: Set the user field in the context.
+
+	NULL initially, this field can be set to any opaque value
+	required by the user. It is copied on clones.
+
+	Does not throw exceptions.
+*/
+void fz_set_user_context(fz_context *ctx, void *user);
+
+/*
+	fz_user_context: Read the user field from the context.
+
+	Does not throw exceptions.
+*/
+void *fz_user_context(fz_context *ctx);
+
+
+/*
 	fz_aa_level: Get the number of bits of antialiasing we are
 	using. Between 0 and 8.
 */
diff --git a/source/fitz/context.c b/source/fitz/context.c
index 44f96993..53f820a1 100644
--- a/source/fitz/context.c
+++ b/source/fitz/context.c
@@ -120,6 +120,7 @@ new_context_phase1(fz_alloc_context *alloc, fz_locks_context *locks)
 	if (!ctx)
 		return NULL;
 	memset(ctx, 0, sizeof *ctx);
+	ctx->user = NULL;
 	ctx->alloc = alloc;
 	ctx->locks = locks;
 
@@ -223,6 +224,7 @@ fz_clone_context_internal(fz_context *ctx)
 	fz_copy_aa_context(new_ctx, ctx);
 
 	/* Keep thread lock checking happy by copying pointers first and locking under new context */
+	new_ctx->user = ctx->user;
 	new_ctx->store = ctx->store;
 	new_ctx->store = fz_keep_store_context(new_ctx);
 	new_ctx->glyph_cache = ctx->glyph_cache;
@@ -253,3 +255,17 @@ fz_gen_id(fz_context *ctx)
 	fz_unlock(ctx, FZ_LOCK_ALLOC);
 	return id;
 }
+
+void fz_set_user_context(fz_context *ctx, void *user)
+{
+	if (ctx != NULL)
+		ctx->user = user;
+}
+
+void *fz_user_context(fz_context *ctx)
+{
+	if (ctx == NULL)
+		return NULL;
+
+	return ctx->user;
+}