assert() function arguments

5 files changed, 56 insertions, 3 deletions

diff --git a/src/font.c b/src/font.c
index 719d7ff..d333189 100644
--- a/src/font.c
+++ b/src/font.c
@@ -21,6 +21,7 @@
 
 #include "font.h"
 
+#include <assert.h>
 #include <limits.h>
 #include <stdio.h>
 #include <string.h>
@@ -53,6 +54,8 @@ font_list(FILE *stream)
 {
 	size_t i;
 
+	assert(stream);
+
 	for (i = 0; i < *(&fonts + 1) - fonts; ++i) {
 		fprintf(stream, "%s\n", fonts[i]->name);
 	}
@@ -81,6 +84,8 @@ font_find(const char *name)
 {
 	size_t i;
 
+	assert(name);
+
 	if (!name) {
 		return NULL;
 	}
@@ -96,12 +101,16 @@ font_find(const char *name)
 int
 font_get_width(const struct font *font)
 {
+	assert(font);
+
 	return font->desc.width;
 }
 
 int
 font_get_height(const struct font *font)
 {
+	assert(font);
+
 	return font->desc.height;
 }
 
@@ -116,6 +125,11 @@ font_render(const struct font *font, png_const_colorp fg, png_const_colorp bg,
 	size_t        byte;
 	unsigned char font_ch;
 
+	assert(font);
+	assert(fg);
+	assert(bg);
+	assert(rows && *rows);
+
 	for (y = 0, r = row * FONT_H(font); y < FONT_H(font); ++y, ++r) {
 		for (x = 0, c = col * FONT_W(font); x < FONT_W(font); ++x, ++c){
 			byte = ((ch * FONT_H(font)) + y) * FONT_W_BYTES(font) +
diff --git a/src/image.c b/src/image.c
index 47bc94c..626ffa7 100644
--- a/src/image.c
+++ b/src/image.c
@@ -21,6 +21,7 @@
 
 #include "image.h"
 
+#include <assert.h>
 #include <stdlib.h>
 #include <stdio.h>
 
@@ -42,6 +43,8 @@ image_new(const char *file_name)
 {
 	struct image *image;
 
+	assert(file_name && *file_name);
+
 	image = calloc(1, sizeof(*image));
 	if (!image) {
 		error(_("Cannot allocate memory for image object"));
@@ -87,6 +90,10 @@ image_render(struct image *image, const struct text *text,
 	png_bytepp rows;
 	size_t     i;
 
+	assert(image);
+	assert(text);
+	assert(font);
+
 	width  = text_get_width(text)  * font_get_width(font);
 	height = text_get_height(text) * font_get_height(font);
 
@@ -116,6 +123,8 @@ image_destroy(struct image **image_p)
 {
 	struct image *image;
 
+	assert(image_p && *image_p);
+
 	image = *image_p;
 
 	if (image->fp) {
diff --git a/src/output.c b/src/output.c
index 0d8341c..77bda63 100644
--- a/src/output.c
+++ b/src/output.c
@@ -21,6 +21,7 @@
 
 #include "output.h"
 
+#include <assert.h>
 #include <stdarg.h>
 #include <stdio.h>
 
@@ -31,6 +32,8 @@ static const char *_program_name;
 void
 set_program_name(const char *name)
 {
+	assert(name && *name);
+
 	_program_name = name;
 }
 
@@ -39,6 +42,8 @@ error(const char *format, ...)
 {
 	va_list ap;
 
+	assert(format);
+
 	fprintf(stderr, _("%s: Error: "), _program_name);
 	va_start(ap, format);
 	vfprintf(stderr, format, ap);
diff --git a/src/sgr.c b/src/sgr.c
index 4017b72..b768e96 100644
--- a/src/sgr.c
+++ b/src/sgr.c
@@ -21,6 +21,7 @@
 
 #include "sgr.h"
 
+#include <assert.h>
 #include <stdlib.h>
 #include <string.h>
 
@@ -57,6 +58,10 @@ sgr(unsigned char *param, png_colorp fg, png_colorp bg)
 	unsigned char *p;
 	int            i;
 
+	assert(param);
+	assert(fg);
+	assert(bg);
+
 	end = 0;
 	for (p = param; param; ++param) {
 		if (*param == ';' || *param == ':' || *param == '\0') {
diff --git a/src/text.c b/src/text.c
index f5ddaba..b288043 100644
--- a/src/text.c
+++ b/src/text.c
@@ -21,6 +21,7 @@
 
 #include "text.h"
 
+#include <assert.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -47,6 +48,10 @@ _getc(struct text *text, FILE *stream, unsigned char *c)
 {
 	int i_c;
 
+	assert(text);
+	assert(stream);
+	assert(c);
+
 	if (text->read == text->size) {
 		text->size += 8192;
 		text->string = realloc(text->string, text->size);
@@ -67,9 +72,8 @@ text_new(FILE *stream)
 	int            eol;
 	unsigned char  c;
 
-	if (!stream) {
-		return NULL;
-	}
+	assert(stream);
+
 	text = calloc(1, sizeof(*text));
 	if (!text) {
 		error(_("Cannot allocate memory for text object"));
@@ -114,24 +118,34 @@ text_new(FILE *stream)
 size_t
 text_get_width(const struct text *text)
 {
+	assert(text);
+
 	return text->width;
 }
 
 size_t
 text_get_height(const struct text *text)
 {
+	assert(text);
+
 	return text->height;
 }
 
 size_t
 text_set_width(struct text *text, size_t width)
 {
+	assert(text);
+	assert(width > 0);
+
 	return text->width = MAX(text->width, width);
 }
 
 size_t
 text_set_height(struct text *text, size_t height)
 {
+	assert(text);
+	assert(height > 0);
+
 	return text->height = MAX(text->height, height);
 }
 
@@ -146,6 +160,10 @@ text_render(const struct text *text, const struct font *font, png_bytepp rows)
 	png_color  fg = {170, 170, 170};
 	png_color  bg = {  0,   0,   0};
 
+	assert(text);
+	assert(font);
+	assert(rows);
+
 	string_start = calloc(strlen((char *) text->string) + 1,
 			sizeof(*text->string));
 	if (!string_start) {
@@ -198,6 +216,8 @@ text_destroy(struct text **text_p)
 {
 	struct text *text;
 
+	assert(text_p && *text_p);
+
 	text = *text_p;
 
 	free(text->string);