1
2
3 /*
4 * io.c
5 *
6 * Implements the simple I/O 'helper' routines.
7 *
8 * Not really essential, but these routines were used extensively in GD,
9 * so they were moved here. They also make IOCtx calls look better...
10 *
11 * Written (or, at least, moved) 1999, Philip Warner.
12 *
13 */
14
15 #include <math.h>
16 #include <string.h>
17 #include <stdlib.h>
18 #include "gd.h"
19
20 /* Use this for commenting out debug-print statements. */
21 /* Just use the first '#define' to allow all the prints... */
22 /*#define IO_DBG(s) (s) */
23 #define IO_DBG(s)
24
25
26 #define GD_IO_EOF_CHK(r) \
27 if (r == EOF) { \
28 return 0; \
29 } \
30
31 /*
32 * Write out a word to the I/O context pointer
33 */
Putword(int w,gdIOCtx * ctx)34 void Putword (int w, gdIOCtx * ctx)
35 {
36 unsigned char buf[2];
37
38 buf[0] = w & 0xff;
39 buf[1] = (w / 256) & 0xff;
40 (ctx->putBuf) (ctx, (char *) buf, 2);
41 }
42
Putchar(int c,gdIOCtx * ctx)43 void Putchar (int c, gdIOCtx * ctx)
44 {
45 (ctx->putC) (ctx, c & 0xff);
46 }
47
gdPutC(const unsigned char c,gdIOCtx * ctx)48 void gdPutC (const unsigned char c, gdIOCtx * ctx)
49 {
50 (ctx->putC) (ctx, c);
51 }
52
gdPutWord(int w,gdIOCtx * ctx)53 void gdPutWord (int w, gdIOCtx * ctx)
54 {
55 IO_DBG (gd_error("Putting word..."));
56 (ctx->putC) (ctx, (unsigned char) (w >> 8));
57 (ctx->putC) (ctx, (unsigned char) (w & 0xFF));
58 IO_DBG (gd_error("put."));
59 }
60
gdPutInt(int w,gdIOCtx * ctx)61 void gdPutInt (int w, gdIOCtx * ctx)
62 {
63 IO_DBG (gd_error("Putting int..."));
64 (ctx->putC) (ctx, (unsigned char) (w >> 24));
65 (ctx->putC) (ctx, (unsigned char) ((w >> 16) & 0xFF));
66 (ctx->putC) (ctx, (unsigned char) ((w >> 8) & 0xFF));
67 (ctx->putC) (ctx, (unsigned char) (w & 0xFF));
68 IO_DBG (gd_error("put."));
69 }
70
gdGetC(gdIOCtx * ctx)71 int gdGetC (gdIOCtx * ctx)
72 {
73 return ((ctx->getC) (ctx));
74 }
75
gdGetByte(int * result,gdIOCtx * ctx)76 int gdGetByte (int *result, gdIOCtx * ctx)
77 {
78 int r;
79 r = (ctx->getC) (ctx);
80 GD_IO_EOF_CHK(r);
81 *result = r;
82 return 1;
83 }
84
gdGetWord(int * result,gdIOCtx * ctx)85 int gdGetWord (int *result, gdIOCtx * ctx)
86 {
87 int r;
88 r = (ctx->getC) (ctx);
89 GD_IO_EOF_CHK(r);
90 *result = r << 8;
91 r = (ctx->getC) (ctx);
92 GD_IO_EOF_CHK(r);
93 *result += r;
94 return 1;
95 }
96
97
gdGetWordLSB(signed short int * result,gdIOCtx * ctx)98 int gdGetWordLSB(signed short int *result, gdIOCtx *ctx)
99 {
100 int high = 0, low = 0;
101 low = (ctx->getC) (ctx);
102 if (low == EOF) {
103 return 0;
104 }
105
106 high = (ctx->getC) (ctx);
107 if (high == EOF) {
108 return 0;
109 }
110
111 if (result) {
112 *result = (high << 8) | low;
113 }
114
115 return 1;
116 }
117
gdGetInt(int * result,gdIOCtx * ctx)118 int gdGetInt (int *result, gdIOCtx * ctx)
119 {
120 unsigned int r;
121 r = (ctx->getC) (ctx);
122 GD_IO_EOF_CHK(r);
123 *result = r << 24;
124
125 r = (ctx->getC) (ctx);
126 GD_IO_EOF_CHK(r);
127 *result += r << 16;
128
129 r = (ctx->getC) (ctx);
130 if (r == EOF) {
131 return 0;
132 }
133 *result += r << 8;
134
135 r = (ctx->getC) (ctx);
136 GD_IO_EOF_CHK(r);
137 *result += r;
138
139 return 1;
140 }
141
gdGetIntLSB(signed int * result,gdIOCtx * ctx)142 int gdGetIntLSB(signed int *result, gdIOCtx *ctx)
143 {
144 unsigned int c;
145 unsigned int r = 0;
146
147 c = (ctx->getC) (ctx);
148 if (c == EOF) {
149 return 0;
150 }
151 r |= (c << 24);
152 r >>= 8;
153
154 c = (ctx->getC) (ctx);
155 if (c == EOF) {
156 return 0;
157 }
158 r |= (c << 24);
159 r >>= 8;
160
161 c = (ctx->getC) (ctx);
162 if (c == EOF) {
163 return 0;
164 }
165 r |= (c << 24);
166 r >>= 8;
167
168 c = (ctx->getC) (ctx);
169 if (c == EOF) {
170 return 0;
171 }
172 r |= (c << 24);
173
174 if (result) {
175 *result = (signed int)r;
176 }
177
178 return 1;
179 }
180
gdPutBuf(const void * buf,int size,gdIOCtx * ctx)181 int gdPutBuf (const void *buf, int size, gdIOCtx * ctx)
182 {
183 IO_DBG (gd_error("Putting buf..."));
184 return (ctx->putBuf) (ctx, buf, size);
185 IO_DBG (gd_error("put."));
186 }
187
gdGetBuf(void * buf,int size,gdIOCtx * ctx)188 int gdGetBuf (void *buf, int size, gdIOCtx * ctx)
189 {
190 return (ctx->getBuf) (ctx, buf, size);
191 }
192
gdSeek(gdIOCtx * ctx,const int pos)193 int gdSeek (gdIOCtx * ctx, const int pos)
194 {
195 IO_DBG (gd_error("Seeking..."));
196 return ((ctx->seek) (ctx, pos));
197 IO_DBG (gd_error("Done."));
198 }
199
gdTell(gdIOCtx * ctx)200 long gdTell (gdIOCtx * ctx)
201 {
202 IO_DBG (gd_error("Telling..."));
203 return ((ctx->tell) (ctx));
204 IO_DBG (gd_error ("told."));
205 }
206
