Add lots of consts.

In general, we should use 'const fz_blah' in device calls whenever
the callee should not alter the fz_blah.

Push this through. This shows up various places where we fz_keep
and fz_drop these const things.

I've updated the fz_keep and fz_drops with appropriate casts
to remove the consts. We may need to do the union dance to avoid
the consts for some compilers, but will only do that if required.

I think this is nicer overall, even allowing for the const<->no const
problems.

2 files changed, 31 insertions, 31 deletions

diff --git a/source/pdf/pdf-colorspace.c b/source/pdf/pdf-colorspace.c
index 321b224b..b8c2e1cc 100644
--- a/source/pdf/pdf-colorspace.c
+++ b/source/pdf/pdf-colorspace.c
@@ -53,7 +53,7 @@ static inline float fung(float x)
 }
 
 static void
-lab_to_rgb(fz_context *ctx, fz_colorspace *cs, const float *lab, float *rgb)
+lab_to_rgb(fz_context *ctx, const fz_colorspace *cs, const float *lab, float *rgb)
 {
 	/* input is in range (0..100, -128..127, -128..127) not (0..1, 0..1, 0..1) */
 	float lstar, astar, bstar, l, m, n, x, y, z, r, g, b;
@@ -75,7 +75,7 @@ lab_to_rgb(fz_context *ctx, fz_colorspace *cs, const float *lab, float *rgb)
 }
 
 static void
-rgb_to_lab(fz_context *ctx, fz_colorspace *cs, const float *rgb, float *lab)
+rgb_to_lab(fz_context *ctx, const fz_colorspace *cs, const float *rgb, float *lab)
 {
 	fz_warn(ctx, "cannot convert into L*a*b colorspace");
 	lab[0] = rgb[0];
@@ -95,7 +95,7 @@ struct separation
 };
 
 static void
-separation_to_rgb(fz_context *ctx, fz_colorspace *cs, const float *color, float *rgb)
+separation_to_rgb(fz_context *ctx, const fz_colorspace *cs, const float *color, float *rgb)
 {
 	struct separation *sep = cs->data;
 	float alt[FZ_MAX_COLORS];
@@ -104,7 +104,7 @@ separation_to_rgb(fz_context *ctx, fz_colorspace *cs, const float *color, float
 }
 
 static void
-free_separation(fz_context *ctx, fz_colorspace *cs)
+free_separation(fz_context *ctx, const fz_colorspace *cs)
 {
 	struct separation *sep = cs->data;
 	fz_drop_colorspace(ctx, sep->base);
@@ -165,7 +165,7 @@ load_separation(fz_context *ctx, pdf_document *doc, pdf_obj *array)
 }
 
 int
-pdf_is_tint_colorspace(fz_context *ctx, fz_colorspace *cs)
+pdf_is_tint_colorspace(fz_context *ctx, const fz_colorspace *cs)
 {
 	return cs && cs->to_rgb == separation_to_rgb;
 }
diff --git a/source/pdf/pdf-device.c b/source/pdf/pdf-device.c
index bcdcb914..da6a141c 100644
--- a/source/pdf/pdf-device.c
+++ b/source/pdf/pdf-device.c
@@ -19,7 +19,7 @@ struct gstate_s
 	void (*on_pop)(fz_context*,pdf_device*,void *);
 	void *on_pop_arg;
 	/* The graphics state proper */
-	fz_colorspace *colorspace[2];
+	const fz_colorspace *colorspace[2];
 	float color[2][4];
 	fz_matrix ctm;
 	fz_stroke_state *stroke_state;
@@ -111,7 +111,7 @@ struct pdf_device_s
 /* Helper functions */
 
 static int
-send_image(fz_context *ctx, pdf_device *pdev, fz_image *image, int mask, int smask)
+send_image(fz_context *ctx, pdf_device *pdev, const fz_image *image, int mask, int smask)
 {
 	fz_pixmap *pixmap = NULL;
 	pdf_obj *imobj = NULL;
@@ -312,7 +312,7 @@ send_image(fz_context *ctx, pdf_device *pdev, fz_image *image, int mask, int sma
 }
 
 static void
-pdf_dev_stroke_state(fz_context *ctx, pdf_device *pdev, fz_stroke_state *stroke_state)
+pdf_dev_stroke_state(fz_context *ctx, pdf_device *pdev, const fz_stroke_state *stroke_state)
 {
 	gstate *gs = CURRENT_GSTATE(pdev);
 
@@ -407,7 +407,7 @@ static const fz_path_processor pdf_dev_path_proc =
 };
 
 static void
-pdf_dev_path(fz_context *ctx, pdf_device *pdev, fz_path *path)
+pdf_dev_path(fz_context *ctx, pdf_device *pdev, const fz_path *path)
 {
 	gstate *gs = CURRENT_GSTATE(pdev);
 
@@ -429,7 +429,7 @@ pdf_dev_ctm(fz_context *ctx, pdf_device *pdev, const fz_matrix *ctm)
 }
 
 static void
-pdf_dev_color(fz_context *ctx, pdf_device *pdev, fz_colorspace *colorspace, float *color, int stroke)
+pdf_dev_color(fz_context *ctx, pdf_device *pdev, const fz_colorspace *colorspace, const float *color, int stroke)
 {
 	int diff = 0;
 	int i;
@@ -550,7 +550,7 @@ pdf_dev_alpha(fz_context *ctx, pdf_device *pdev, float alpha, int stroke)
 }
 
 static void
-pdf_dev_font(fz_context *ctx, pdf_device *pdev, fz_font *font, float size)
+pdf_dev_font(fz_context *ctx, pdf_device *pdev, const fz_font *font, float size)
 {
 	int i;
 	pdf_document *doc = pdev->doc;
@@ -775,7 +775,7 @@ pdf_dev_end_text(fz_context *ctx, pdf_device *pdev)
 }
 
 static int
-pdf_dev_new_form(fz_context *ctx, pdf_obj **form_ref, pdf_device *pdev, const fz_rect *bbox, int isolated, int knockout, float alpha, fz_colorspace *colorspace)
+pdf_dev_new_form(fz_context *ctx, pdf_obj **form_ref, pdf_device *pdev, const fz_rect *bbox, int isolated, int knockout, float alpha, const fz_colorspace *colorspace)
 {
 	pdf_document *doc = pdev->doc;
 	int num;
@@ -871,8 +871,8 @@ pdf_dev_new_form(fz_context *ctx, pdf_obj **form_ref, pdf_device *pdev, const fz
 /* Entry points */
 
 static void
-pdf_dev_fill_path(fz_context *ctx, fz_device *dev, fz_path *path, int even_odd, const fz_matrix *ctm,
-	fz_colorspace *colorspace, float *color, float alpha)
+pdf_dev_fill_path(fz_context *ctx, fz_device *dev, const fz_path *path, int even_odd, const fz_matrix *ctm,
+	const fz_colorspace *colorspace, const float *color, float alpha)
 {
 	pdf_device *pdev = (pdf_device*)dev;
 	gstate *gs = CURRENT_GSTATE(pdev);
@@ -886,8 +886,8 @@ pdf_dev_fill_path(fz_context *ctx, fz_device *dev, fz_path *path, int even_odd,
 }
 
 static void
-pdf_dev_stroke_path(fz_context *ctx, fz_device *dev, fz_path *path, fz_stroke_state *stroke, const fz_matrix *ctm,
-	fz_colorspace *colorspace, float *color, float alpha)
+pdf_dev_stroke_path(fz_context *ctx, fz_device *dev, const fz_path *path, const fz_stroke_state *stroke, const fz_matrix *ctm,
+	const fz_colorspace *colorspace, const float *color, float alpha)
 {
 	pdf_device *pdev = (pdf_device*)dev;
 	gstate *gs = CURRENT_GSTATE(pdev);
@@ -902,7 +902,7 @@ pdf_dev_stroke_path(fz_context *ctx, fz_device *dev, fz_path *path, fz_stroke_st
 }
 
 static void
-pdf_dev_clip_path(fz_context *ctx, fz_device *dev, fz_path *path, const fz_rect *rect, int even_odd, const fz_matrix *ctm)
+pdf_dev_clip_path(fz_context *ctx, fz_device *dev, const fz_path *path, const fz_rect *rect, int even_odd, const fz_matrix *ctm)
 {
 	pdf_device *pdev = (pdf_device*)dev;
 	gstate *gs;
@@ -916,7 +916,7 @@ pdf_dev_clip_path(fz_context *ctx, fz_device *dev, fz_path *path, const fz_rect
 }
 
 static void
-pdf_dev_clip_stroke_path(fz_context *ctx, fz_device *dev, fz_path *path, const fz_rect *rect, fz_stroke_state *stroke, const fz_matrix *ctm)
+pdf_dev_clip_stroke_path(fz_context *ctx, fz_device *dev, const fz_path *path, const fz_rect *rect, const fz_stroke_state *stroke, const fz_matrix *ctm)
 {
 	pdf_device *pdev = (pdf_device*)dev;
 	gstate *gs;
@@ -934,8 +934,8 @@ pdf_dev_clip_stroke_path(fz_context *ctx, fz_device *dev, fz_path *path, const f
 }
 
 static void
-pdf_dev_fill_text(fz_context *ctx, fz_device *dev, fz_text *text, const fz_matrix *ctm,
-		fz_colorspace *colorspace, float *color, float alpha)
+pdf_dev_fill_text(fz_context *ctx, fz_device *dev, const fz_text *text, const fz_matrix *ctm,
+		const fz_colorspace *colorspace, const float *color, float alpha)
 {
 	pdf_device *pdev = (pdf_device*)dev;
 	fz_text_span *span;
@@ -957,8 +957,8 @@ pdf_dev_fill_text(fz_context *ctx, fz_device *dev, fz_text *text, const fz_matri
 }
 
 static void
-pdf_dev_stroke_text(fz_context *ctx, fz_device *dev, fz_text *text, fz_stroke_state *stroke, const fz_matrix *ctm,
-		fz_colorspace *colorspace, float *color, float alpha)
+pdf_dev_stroke_text(fz_context *ctx, fz_device *dev, const fz_text *text, const fz_stroke_state *stroke, const fz_matrix *ctm,
+		const fz_colorspace *colorspace, const float *color, float alpha)
 {
 	pdf_device *pdev = (pdf_device*)dev;
 	fz_text_span *span;
@@ -980,7 +980,7 @@ pdf_dev_stroke_text(fz_context *ctx, fz_device *dev, fz_text *text, fz_stroke_st
 }
 
 static void
-pdf_dev_clip_text(fz_context *ctx, fz_device *dev, fz_text *text, const fz_matrix *ctm)
+pdf_dev_clip_text(fz_context *ctx, fz_device *dev, const fz_text *text, const fz_matrix *ctm)
 {
 	pdf_device *pdev = (pdf_device*)dev;
 	fz_text_span *span;
@@ -999,7 +999,7 @@ pdf_dev_clip_text(fz_context *ctx, fz_device *dev, fz_text *text, const fz_matri
 }
 
 static void
-pdf_dev_clip_stroke_text(fz_context *ctx, fz_device *dev, fz_text *text, fz_stroke_state *stroke, const fz_matrix *ctm)
+pdf_dev_clip_stroke_text(fz_context *ctx, fz_device *dev, const fz_text *text, const fz_stroke_state *stroke, const fz_matrix *ctm)
 {
 	pdf_device *pdev = (pdf_device*)dev;
 	fz_text_span *span;
@@ -1018,7 +1018,7 @@ pdf_dev_clip_stroke_text(fz_context *ctx, fz_device *dev, fz_text *text, fz_stro
 }
 
 static void
-pdf_dev_ignore_text(fz_context *ctx, fz_device *dev, fz_text *text, const fz_matrix *ctm)
+pdf_dev_ignore_text(fz_context *ctx, fz_device *dev, const fz_text *text, const fz_matrix *ctm)
 {
 	pdf_device *pdev = (pdf_device*)dev;
 	fz_text_span *span;
@@ -1037,7 +1037,7 @@ pdf_dev_ignore_text(fz_context *ctx, fz_device *dev, fz_text *text, const fz_mat
 }
 
 static void
-pdf_dev_fill_image(fz_context *ctx, fz_device *dev, fz_image *image, const fz_matrix *ctm, float alpha)
+pdf_dev_fill_image(fz_context *ctx, fz_device *dev, const fz_image *image, const fz_matrix *ctm, float alpha)
 {
 	pdf_device *pdev = (pdf_device*)dev;
 	int num;
@@ -1055,7 +1055,7 @@ pdf_dev_fill_image(fz_context *ctx, fz_device *dev, fz_image *image, const fz_ma
 }
 
 static void
-pdf_dev_fill_shade(fz_context *ctx, fz_device *dev, fz_shade *shade, const fz_matrix *ctm, float alpha)
+pdf_dev_fill_shade(fz_context *ctx, fz_device *dev, const fz_shade *shade, const fz_matrix *ctm, float alpha)
 {
 	pdf_device *pdev = (pdf_device*)dev;
 
@@ -1064,8 +1064,8 @@ pdf_dev_fill_shade(fz_context *ctx, fz_device *dev, fz_shade *shade, const fz_ma
 }
 
 static void
-pdf_dev_fill_image_mask(fz_context *ctx, fz_device *dev, fz_image *image, const fz_matrix *ctm,
-fz_colorspace *colorspace, float *color, float alpha)
+pdf_dev_fill_image_mask(fz_context *ctx, fz_device *dev, const fz_image *image, const fz_matrix *ctm,
+		const fz_colorspace *colorspace, const float *color, float alpha)
 {
 	pdf_device *pdev = (pdf_device*)dev;
 	gstate *gs = CURRENT_GSTATE(pdev);
@@ -1085,7 +1085,7 @@ fz_colorspace *colorspace, float *color, float alpha)
 }
 
 static void
-pdf_dev_clip_image_mask(fz_context *ctx, fz_device *dev, fz_image *image, const fz_rect *rect, const fz_matrix *ctm)
+pdf_dev_clip_image_mask(fz_context *ctx, fz_device *dev, const fz_image *image, const fz_rect *rect, const fz_matrix *ctm)
 {
 	pdf_device *pdev = (pdf_device*)dev;
 
@@ -1105,7 +1105,7 @@ pdf_dev_pop_clip(fz_context *ctx, fz_device *dev)
 }
 
 static void
-pdf_dev_begin_mask(fz_context *ctx, fz_device *dev, const fz_rect *bbox, int luminosity, fz_colorspace *colorspace, float *color)
+pdf_dev_begin_mask(fz_context *ctx, fz_device *dev, const fz_rect *bbox, int luminosity, const fz_colorspace *colorspace, const float *color)
 {
 	pdf_device *pdev = (pdf_device*)dev;
 	pdf_document *doc = pdev->doc;