Bug Summary

File:bitmap/fontink.c
Location:line 142, column 18
Description:Dereference of null pointer

Annotated Source Code

1/*
2
3Copyright 1990, 1998 The Open Group
4
5Permission to use, copy, modify, distribute, and sell this software and its
6documentation for any purpose is hereby granted without fee, provided that
7the above copyright notice appear in all copies and that both that
8copyright notice and this permission notice appear in supporting
9documentation.
10
11The above copyright notice and this permission notice shall be included
12in all copies or substantial portions of the Software.
13
14THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
15OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
16MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
17IN NO EVENT SHALL THE OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR
18OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20OTHER DEALINGS IN THE SOFTWARE.
21
22Except as contained in this notice, the name of The Open Group shall
23not be used in advertising or otherwise to promote the sale, use or
24other dealings in this Software without prior written authorization
25from The Open Group.
26
27*/
28
29/*
30 * Author: Keith Packard, MIT X Consortium
31 */
32
33#ifdef HAVE_CONFIG_H1
34#include <config.h>
35#endif
36
37#include <X11/fonts/fntfilst.h>
38#include <X11/fonts/bitmap.h>
39#include <X11/fonts/bdfint.h>
40
41static unsigned char ink_mask_msb[8] = {
42 0x80, 0x40, 0x20, 0x10, 0x08, 0x04, 0x02, 0x01,
43};
44
45static unsigned char ink_mask_lsb[8] = {
46 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80,
47};
48
49void
50FontCharInkMetrics(FontPtr pFont, CharInfoPtr pCI, xCharInfo *pInk)
51{
52 int leftBearing,
53 ascent,
54 descent;
55 register int vpos,
56 hpos,
57 bpos = 0;
58 int bitmapByteWidth,
59 bitmapByteWidthPadded;
60 int bitmapBitWidth;
61 int span;
62 register unsigned char *p;
63 unsigned char *ink_mask = 0;
64 register int bmax;
65 register unsigned char charbits;
66
67 if (pFont->bit == MSBFirst1)
1
Taking false branch
68 ink_mask = ink_mask_msb;
69 else if (pFont->bit == LSBFirst0)
2
Taking false branch
70 ink_mask = ink_mask_lsb;
71 pInk->characterWidth = pCI->metrics.characterWidth;
72 pInk->attributes = pCI->metrics.attributes;
73
74 leftBearing = pCI->metrics.leftSideBearing;
75 ascent = pCI->metrics.ascent;
76 descent = pCI->metrics.descent;
77 bitmapBitWidth = GLYPHWIDTHPIXELS(pCI)((pCI)->metrics.rightSideBearing - (pCI)->metrics.leftSideBearing
)
;
78 bitmapByteWidth = GLYPHWIDTHBYTES(pCI)(((((pCI)->metrics.rightSideBearing - (pCI)->metrics.leftSideBearing
))+7) >> 3)
;
79 bitmapByteWidthPadded = BYTES_PER_ROW(bitmapBitWidth, pFont->glyph)((pFont->glyph) == 1 ? (((bitmapBitWidth)+7)>>3) :(pFont
->glyph) == 2 ? ((((bitmapBitWidth)+15)>>3)&~1) :
(pFont->glyph) == 4 ? ((((bitmapBitWidth)+31)>>3)&
~3) :(pFont->glyph) == 8 ? ((((bitmapBitWidth)+63)>>
3)&~7) : 0)
;
80 span = bitmapByteWidthPadded - bitmapByteWidth;
81
82 p = (unsigned char *) pCI->bits;
83 for (vpos = descent + ascent; --vpos >= 0;) {
3
Loop condition is true. Entering loop body
84 for (hpos = bitmapByteWidth; --hpos >= 0;) {
4
Loop condition is true. Entering loop body
85 if (*p++ != 0)
5
Taking true branch
86 goto found_ascent;
6
Control jumps to line 99
87 }
88 p += span;
89 }
90 /*
91 * special case -- font with no bits gets all zeros
92 */
93 pInk->leftSideBearing = leftBearing;
94 pInk->rightSideBearing = leftBearing;
95 pInk->ascent = 0;
96 pInk->descent = 0;
97 return;
98found_ascent:
99 pInk->ascent = vpos - descent + 1;
100
101 p = ((unsigned char *) pCI->bits) + bitmapByteWidthPadded *
102 (descent + ascent - 1) + bitmapByteWidth;
103
104 for (vpos = descent + ascent; --vpos >= 0;) {
7
Loop condition is false. Execution continues on line 112
105 for (hpos = bitmapByteWidth; --hpos >= 0;) {
106 if (*--p != 0)
107 goto found_descent;
108 }
109 p -= span;
110 }
111found_descent:
112 pInk->descent = vpos - ascent + 1;
113
114 bmax = 8;
115 for (hpos = 0; hpos < bitmapByteWidth; hpos++) {
8
Assuming 'hpos' is >= 'bitmapByteWidth'
9
Loop condition is false. Execution continues on line 131
116 charbits = 0;
117 p = (unsigned char *) pCI->bits + hpos;
118 for (vpos = descent + ascent; --vpos >= 0; p += bitmapByteWidthPadded)
119 charbits |= *p;
120 if (charbits) {
121 if (hpos == bitmapByteWidth - 1)
122 bmax = bitmapBitWidth - (hpos << 3);
123 p = ink_mask;
124 for (bpos = bmax; --bpos >= 0;) {
125 if (charbits & *p++)
126 goto found_left;
127 }
128 }
129 }
130found_left:
131 pInk->leftSideBearing = leftBearing + (hpos << 3) + bmax - bpos - 1;
132
133 bmax = bitmapBitWidth - ((bitmapByteWidth - 1) << 3);
134 for (hpos = bitmapByteWidth; --hpos >= 0;) {
10
Loop condition is true. Entering loop body
13
Loop condition is true. Entering loop body
135 charbits = 0;
136 p = (unsigned char *) pCI->bits + hpos;
137 for (vpos = descent + ascent; --vpos >= 0; p += bitmapByteWidthPadded)
11
Loop condition is false. Execution continues on line 139
14
Loop condition is true. Entering loop body
15
Loop condition is false. Execution continues on line 139
138 charbits |= *p;
139 if (charbits) {
12
Taking false branch
16
Assuming 'charbits' is not equal to 0
17
Taking true branch
140 p = ink_mask + bmax;
141 for (bpos = bmax; --bpos >= 0;) {
18
Loop condition is true. Entering loop body
142 if (charbits & *--p)
19
Dereference of null pointer
143 goto found_right;
144 }
145 }
146 bmax = 8;
147 }
148found_right:
149 pInk->rightSideBearing = leftBearing + (hpos << 3) + bpos + 1;
150}
151
152#define ISBITONMSB(x, line)((line)[(x)/8] & (1 << (7 -((x)%8)))) ((line)[(x)/8] & (1 << (7-((x)%8))))
153#define SETBITMSB(x, line)((line)[(x)/8] |= (1 << (7 -((x)%8)))) ((line)[(x)/8] |= (1 << (7-((x)%8))))
154#define ISBITONLSB(x, line)((line)[(x)/8] & (1 << ((x)%8))) ((line)[(x)/8] & (1 << ((x)%8)))
155#define SETBITLSB(x, line)((line)[(x)/8] |= (1 << ((x)%8))) ((line)[(x)/8] |= (1 << ((x)%8)))
156
157#define Min(a,b)((a)<(b)?(a):(b)) ((a)<(b)?(a):(b))
158#define Max(a,b)((a)>(b)?(a):(b)) ((a)>(b)?(a):(b))
159
160void
161FontCharReshape(FontPtr pFont, CharInfoPtr pSrc, CharInfoPtr pDst)
162{
163 int x,
164 y;
165 unsigned char *in_line,
166 *out_line;
167 unsigned char *oldglyph,
168 *newglyph;
169 int inwidth;
170 int outwidth,
171 outheight;
172 int out_bytes,
173 in_bytes;
174 int y_min,
175 y_max,
176 x_min,
177 x_max;
178
179 newglyph = (unsigned char *) pDst->bits;
180 outwidth = pDst->metrics.rightSideBearing - pDst->metrics.leftSideBearing;
181 outheight = pDst->metrics.descent + pDst->metrics.ascent;
182 out_bytes = BYTES_PER_ROW(outwidth, pFont->glyph)((pFont->glyph) == 1 ? (((outwidth)+7)>>3) :(pFont->
glyph) == 2 ? ((((outwidth)+15)>>3)&~1) :(pFont->
glyph) == 4 ? ((((outwidth)+31)>>3)&~3) :(pFont->
glyph) == 8 ? ((((outwidth)+63)>>3)&~7) : 0)
;
183
184 oldglyph = (unsigned char *) pSrc->bits;
185 inwidth = pSrc->metrics.rightSideBearing - pSrc->metrics.leftSideBearing;
186 in_bytes = BYTES_PER_ROW(inwidth, pFont->glyph)((pFont->glyph) == 1 ? (((inwidth)+7)>>3) :(pFont->
glyph) == 2 ? ((((inwidth)+15)>>3)&~1) :(pFont->
glyph) == 4 ? ((((inwidth)+31)>>3)&~3) :(pFont->
glyph) == 8 ? ((((inwidth)+63)>>3)&~7) : 0)
;
187
188 bzero(newglyph, out_bytes * outheight)memset(newglyph,0,out_bytes * outheight);
189 in_line = oldglyph;
190 out_line = newglyph;
191 y_min = Max(-pSrc->metrics.ascent, -pDst->metrics.ascent)((-pSrc->metrics.ascent)>(-pDst->metrics.ascent)?(-pSrc
->metrics.ascent):(-pDst->metrics.ascent))
;
192 y_max = Min(pSrc->metrics.descent, pDst->metrics.descent)((pSrc->metrics.descent)<(pDst->metrics.descent)?(pSrc
->metrics.descent):(pDst->metrics.descent))
;
193 x_min = Max(pSrc->metrics.leftSideBearing, pDst->metrics.leftSideBearing)((pSrc->metrics.leftSideBearing)>(pDst->metrics.leftSideBearing
)?(pSrc->metrics.leftSideBearing):(pDst->metrics.leftSideBearing
))
;
194 x_max = Min(pSrc->metrics.rightSideBearing, pDst->metrics.rightSideBearing)((pSrc->metrics.rightSideBearing)<(pDst->metrics.rightSideBearing
)?(pSrc->metrics.rightSideBearing):(pDst->metrics.rightSideBearing
))
;
195 in_line += (y_min + pSrc->metrics.ascent) * in_bytes;
196 out_line += (y_min + pDst->metrics.ascent) * out_bytes;
197 if (pFont->bit == MSBFirst1) {
198 for (y = y_min; y < y_max; y++) {
199 for (x = x_min; x < x_max; x++) {
200 if (ISBITONMSB(x - pSrc->metrics.leftSideBearing, in_line)((in_line)[(x - pSrc->metrics.leftSideBearing)/8] & (1
<< (7 -((x - pSrc->metrics.leftSideBearing)%8))))
)
201 SETBITMSB(x - pDst->metrics.leftSideBearing, out_line)((out_line)[(x - pDst->metrics.leftSideBearing)/8] |= (1 <<
(7 -((x - pDst->metrics.leftSideBearing)%8))))
;
202 }
203 in_line += in_bytes;
204 out_line += out_bytes;
205 }
206 } else {
207 for (y = y_min; y < y_max; y++) {
208 for (x = x_min; x < x_max; x++) {
209 if (ISBITONLSB(x - pSrc->metrics.leftSideBearing, in_line)((in_line)[(x - pSrc->metrics.leftSideBearing)/8] & (1
<< ((x - pSrc->metrics.leftSideBearing)%8)))
)
210 SETBITLSB(x - pDst->metrics.leftSideBearing, out_line)((out_line)[(x - pDst->metrics.leftSideBearing)/8] |= (1 <<
((x - pDst->metrics.leftSideBearing)%8)))
;
211 }
212 in_line += in_bytes;
213 out_line += out_bytes;
214 }
215 }
216}