test/text-zero-len.c

   1 /*
   2  * Copyright © 2006 Red Hat, Inc.
   3  *
   4  * Permission to use, copy, modify, distribute, and sell this software
   5  * and its documentation for any purpose is hereby granted without
   6  * fee, provided that the above copyright notice appear in all copies
   7  * and that both that copyright notice and this permission notice
   8  * appear in supporting documentation, and that the name of
   9  * Red Hat, Inc. not be used in advertising or publicity pertaining to
  10  * distribution of the software without specific, written prior
  11  * permission. Red Hat, Inc. makes no representations about the
  12  * suitability of this software for any purpose.  It is provided "as
  13  * is" without express or implied warranty.
  14  *
  15  * RED HAT, INC. DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
  16  * SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
  17  * FITNESS, IN NO EVENT SHALL RED HAT, INC. BE LIABLE FOR ANY SPECIAL,
  18  * INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
  19  * RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
  20  * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR
  21  * IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  22  *
  23  * Author: Behdad Esfahbod <behdad@behdad.org>
  24  */
  25
  26 /* Related bug 5177
  27  *
  28  * In short:
  29  *
  30  * _cairo_atsui_font_text_to_glyph with a zero-sized string crashes.
  31  *
  32  * Moreover, the fallback path in cairo_scaled_font_text_to_glyphs()
  33  * when handling a zero-sized string, allocates a zero-sized glyph array
  34  * and when NULL is returned by malloc, recognizes that as an out-of-memory
  35  * error.  The glibc implementation of malloc() does not return NULL from
  36  * malloc(0), but I don't think it's a safe assumption.
  37  *
  38  * By just bailing out on zero-sized text, we fix both issues.
  39  */
  40
  41 #include "cairo-test.h"
  42
  43 #define NUM_TEXT 20
  44 #define TEXT_SIZE 12
  45
  46 static cairo_test_draw_function_t draw;
  47
  48 cairo_test_t test = {
  49     "text-zero-len",
  50     "Tests show_text and text_path with a zero-sized string",
  51     0, 0,
  52     draw
  53 };
  54
  55 static cairo_bool_t
  56 text_extents_equal (const cairo_text_extents_t *A,
  57                     const cairo_text_extents_t *B)
  58 {
  59     return A->x_bearing == B->x_bearing &&
  60            A->y_bearing == B->y_bearing &&
  61            A->width     == B->width     &&
  62            A->height    == B->height    &&
  63            A->x_advance == B->x_advance &&
  64            A->y_advance == B->y_advance;
  65 }
  66
  67 static cairo_bool_t
  68 font_extents_equal (const cairo_font_extents_t *A,
  69                     const cairo_font_extents_t *B)
  70 {
  71     return A->ascent    == B->ascent        &&
  72            A->descent   == B->descent       &&
  73            A->height    == B->height        &&
  74        A->max_x_advance == B->max_x_advance &&
  75        A->max_y_advance == B->max_y_advance;
  76 }
  77
  78 static cairo_test_status_t
  79 draw (cairo_t *cr, int width, int height)
  80 {
  81     cairo_text_extents_t extents, nil_extents;
  82     cairo_font_extents_t font_extents, nil_font_extents;
  83     cairo_scaled_font_t *scaled_font;
  84
  85     cairo_select_font_face (cr, "Bitstream Vera Sans",
  86                             CAIRO_FONT_SLANT_NORMAL,
  87                             CAIRO_FONT_WEIGHT_NORMAL);
  88     cairo_set_font_size (cr, 16);
  89
  90     cairo_move_to (cr, 10, 25);
  91     cairo_show_text (cr, NULL);
  92     cairo_show_text (cr, "");
  93     cairo_show_glyphs (cr, NULL, 0);
  94     cairo_show_glyphs (cr, (void*)8, 0);
  95
  96     cairo_move_to (cr, 10, 55);
  97     cairo_text_path (cr, NULL);
  98     cairo_text_path (cr, "");
  99     cairo_glyph_path (cr, (void*)8, 0);
 100     cairo_fill (cr);
 101
 102     memset (&nil_extents, 0, sizeof (cairo_text_extents_t));
 103
 104     memset (&extents, 0xff, sizeof (cairo_text_extents_t));
 105     cairo_text_extents (cr, "", &extents);
 106     if (! text_extents_equal (&extents, &nil_extents)) {
 107         cairo_test_log ("Error: cairo_text_extents(\"\"); extents (%g, %g, %g, %g, %g, %g)\n",
 108                         extents.x_bearing, extents.y_bearing,
 109                         extents.width, extents.height,
 110                         extents.x_advance, extents.y_advance);
 111         return CAIRO_TEST_FAILURE;
 112     }
 113
 114     memset (&extents, 0xff, sizeof (cairo_text_extents_t));
 115     cairo_text_extents (cr, NULL, &extents);
 116     if (! text_extents_equal (&extents, &nil_extents)) {
 117         cairo_test_log ("Error: cairo_text_extents(NULL); extents (%g, %g, %g, %g, %g, %g)\n",
 118                         extents.x_bearing, extents.y_bearing,
 119                         extents.width, extents.height,
 120                         extents.x_advance, extents.y_advance);
 121         return CAIRO_TEST_FAILURE;
 122     }
 123
 124     memset (&extents, 0xff, sizeof (cairo_text_extents_t));
 125     cairo_glyph_extents (cr, (void*)8, 0, &extents);
 126     if (! text_extents_equal (&extents, &nil_extents)) {
 127         cairo_test_log ("Error: cairo_glyph_extents(); extents (%g, %g, %g, %g, %g, %g)\n",
 128                         extents.x_bearing, extents.y_bearing,
 129                         extents.width, extents.height,
 130                         extents.x_advance, extents.y_advance);
 131         return CAIRO_TEST_FAILURE;
 132     }
 133
 134     scaled_font = cairo_get_scaled_font (cr);
 135
 136     memset (&extents, 0xff, sizeof (cairo_text_extents_t));
 137     cairo_scaled_font_text_extents (scaled_font, "", &extents);
 138     if (! text_extents_equal (&extents, &nil_extents)) {
 139         cairo_test_log ("Error: cairo_scaled_font_text_extents(\"\"); extents (%g, %g, %g, %g, %g, %g)\n",
 140                         extents.x_bearing, extents.y_bearing,
 141                         extents.width, extents.height,
 142                         extents.x_advance, extents.y_advance);
 143         return CAIRO_TEST_FAILURE;
 144     }
 145
 146     memset (&extents, 0xff, sizeof (cairo_text_extents_t));
 147     cairo_scaled_font_text_extents (scaled_font, NULL, &extents);
 148     if (! text_extents_equal (&extents, &nil_extents)) {
 149         cairo_test_log ("Error: cairo_scaled_font_text_extents(NULL); extents (%g, %g, %g, %g, %g, %g)\n",
 150                         extents.x_bearing, extents.y_bearing,
 151                         extents.width, extents.height,
 152                         extents.x_advance, extents.y_advance);
 153         return CAIRO_TEST_FAILURE;
 154     }
 155
 156     memset (&extents, 0xff, sizeof (cairo_text_extents_t));
 157     cairo_scaled_font_glyph_extents (scaled_font, (void*)8, 0, &extents);
 158     if (! text_extents_equal (&extents, &nil_extents)) {
 159         cairo_test_log ("Error: cairo_scaled_font_glyph_extents(NULL); extents (%g, %g, %g, %g, %g, %g)\n",
 160                         extents.x_bearing, extents.y_bearing,
 161                         extents.width, extents.height,
 162                         extents.x_advance, extents.y_advance);
 163         return CAIRO_TEST_FAILURE;
 164     }
 165
 166     /* Lets also try font size 0 while here */
 167     cairo_set_font_size (cr, 0);
 168
 169     memset (&extents, 0xff, sizeof (cairo_text_extents_t));
 170     cairo_text_extents (cr, "test", &extents);
 171     if (! text_extents_equal (&extents, &nil_extents)) {
 172         cairo_test_log ("Error: cairo_set_font_size(0); cairo_text_extents(\"test\"); extents (%g, %g, %g, %g, %g, %g)\n",
 173                         extents.x_bearing, extents.y_bearing,
 174                         extents.width, extents.height,
 175                         extents.x_advance, extents.y_advance);
 176         return CAIRO_TEST_FAILURE;
 177     }
 178
 179     memset (&nil_font_extents, 0, sizeof (cairo_font_extents_t));
 180
 181     memset (&font_extents, 0xff, sizeof (cairo_font_extents_t));
 182     cairo_font_extents (cr,  &font_extents);
 183     if (! font_extents_equal (&font_extents, &nil_font_extents)) {
 184         cairo_test_log ("Error: cairo_set_font_size(0); cairo_font_extents(); extents (%g, %g, %g, %g, %g)\n",
 185                         font_extents.ascent, font_extents.descent,
 186                         font_extents.height,
 187                         font_extents.max_x_advance, font_extents.max_y_advance);
 188         return CAIRO_TEST_FAILURE;
 189     }
 190
 191     scaled_font = cairo_get_scaled_font (cr);
 192
 193     memset (&font_extents, 0xff, sizeof (cairo_font_extents_t));
 194     cairo_scaled_font_extents (scaled_font,  &font_extents);
 195     if (! font_extents_equal (&font_extents, &nil_font_extents)) {
 196         cairo_test_log ("Error: cairo_set_font_size(0); cairo_scaled_font_extents(); extents (%g, %g, %g, %g, %g)\n",
 197                         font_extents.ascent, font_extents.descent,
 198                         font_extents.height,
 199                         font_extents.max_x_advance, font_extents.max_y_advance);
 200         return CAIRO_TEST_FAILURE;
 201     }
 202
 203     return CAIRO_TEST_SUCCESS;
 204 }
 205
 206 int
 207 main (void)
 208 {
 209     return cairo_test (&test);
 210 }