BLF: fix crash on text input fields

Some strings have known length, others are NULL terminated (len = INT_MAX in this case).

Now font drawing knows to treat INT_MAX special.

1 files changed, 18 insertions, 12 deletions

diff --git a/source/blender/blenfont/intern/blf_font.c b/source/blender/blenfont/intern/blf_font.c
index 7d734653ffc..42717e65d9b 100644
--- a/source/blender/blenfont/intern/blf_font.c
+++ b/source/blender/blenfont/intern/blf_font.c
@@ -174,6 +174,21 @@ static void blf_font_ensure_ascii_table(FontBLF *font)
 	}                                                                            \
 } (void)0
 
+static unsigned verts_needed(const FontBLF *font, const char *str, size_t len)
+{
+	unsigned length = (unsigned)((len == INT_MAX) ? strlen(str) : len);
+	return length * 40;
+	/* (5 shadow + 5 blur) * 4 verts per quad
+	 * TODO: determine exact count of quads, somthing like this: */
+#if 0
+	unsigned quad_ct = 1 + (unsigned)font->blur;
+	if (font->flags & BLF_SHADOW)
+		quad_ct += (unsigned)font->shadow;
+
+	immBegin(GL_QUADS, length * quad_ct * 4);
+#endif
+}
+
 static void blf_font_draw_ex(
         FontBLF *font, const char *str, size_t len, struct ResultBLF *r_info,
         int pen_y)
@@ -189,16 +204,7 @@ static void blf_font_draw_ex(
 
 	blf_font_ensure_ascii_table(font);
 
-	immBeginAtMost(GL_QUADS, (unsigned)len * 40);
-	/* (5 shadow + 5 blur) * 4 verts per quad
-	 * TODO: determine exact count of quads, somthing like this: */
-#if 0
-	unsigned quad_ct = 1 + (unsigned)font->blur;
-	if (font->flags & BLF_SHADOW)
-		quad_ct += (unsigned)font->shadow;
-
-	immBegin(GL_QUADS, (unsigned)len * quad_ct * 4);
-#endif
+	immBeginAtMost(GL_QUADS, verts_needed(font, str, len));
 
 	while ((i < len) && str[i]) {
 		BLF_UTF8_NEXT_FAST(font, g, str, i, c, glyph_ascii_table);
@@ -244,7 +250,7 @@ static void blf_font_draw_ascii_ex(
 
 	blf_font_ensure_ascii_table(font);
 
-	immBeginAtMost(GL_QUADS, (unsigned)len * 40);
+	immBeginAtMost(GL_QUADS, verts_needed(font, str, len));
 
 	while ((c = *(str++)) && len--) {
 		BLI_assert(c < 128);
@@ -284,7 +290,7 @@ int blf_font_draw_mono(FontBLF *font, const char *str, size_t len, int cwidth)
 
 	blf_font_ensure_ascii_table(font);
 
-	immBeginAtMost(GL_QUADS, (unsigned)len * 40);
+	immBeginAtMost(GL_QUADS, verts_needed(font, str, len));
 
 	while ((i < len) && str[i]) {
 		BLF_UTF8_NEXT_FAST(font, g, str, i, c, glyph_ascii_table);