1/*****************************************************************************/
2/* */
3/* fileio.c */
4/* */
5/* File I/O for the od65 object file dump utility */
6/* */
7/* */
8/* */
9/* (C) 1998-2011, Ullrich von Bassewitz */
10/* Roemerstrasse 52 */
11/* D-70794 Filderstadt */
12/* EMail: uz@cc65.org */
13/* */
14/* */
15/* This software is provided 'as-is', without any expressed or implied */
16/* warranty. In no event will the authors be held liable for any damages */
17/* arising from the use of this software. */
18/* */
19/* Permission is granted to anyone to use this software for any purpose, */
20/* including commercial applications, and to alter it and redistribute it */
21/* freely, subject to the following restrictions: */
22/* */
23/* 1. The origin of this software must not be misrepresented; you must not */
24/* claim that you wrote the original software. If you use this software */
25/* in a product, an acknowledgment in the product documentation would be */
26/* appreciated but is not required. */
27/* 2. Altered source versions must be plainly marked as such, and must not */
28/* be misrepresented as being the original software. */
29/* 3. This notice may not be removed or altered from any source */
30/* distribution. */
31/* */
32/*****************************************************************************/
33
34
35
36#include <string.h>
37#include <errno.h>
38
39/* common */
40#include "xmalloc.h"
41
42/* od65 */
43#include "error.h"
44#include "fileio.h"
45
46
47
48/*****************************************************************************/
49/* Code */
50/*****************************************************************************/
51
52
53
54void FileSetPos (FILE* F, unsigned long Pos)
55/* Seek to the given absolute position, fail on errors */
56{
57 if (fseek (F, Pos, SEEK_SET) != 0) {
58 Error ("Cannot seek: %s", strerror (errno));
59 }
60}
61
62
63
64unsigned long FileGetPos (FILE* F)
65/* Return the current file position, fail on errors */
66{
67 long Pos = ftell (F);
68 if (Pos < 0) {
69 Error ("Error in ftell: %s", strerror (errno));
70 }
71 return Pos;
72}
73
74
75
76unsigned Read8 (FILE* F)
77/* Read an 8 bit value from the file */
78{
79 int C = getc (F);
80 if (C == EOF) {
81 Error ("Read error (file corrupt?)");
82 }
83 return C;
84}
85
86
87
88unsigned Read16 (FILE* F)
89/* Read a 16 bit value from the file */
90{
91 unsigned Lo = Read8 (F);
92 unsigned Hi = Read8 (F);
93 return (Hi << 8) | Lo;
94}
95
96
97
98unsigned long Read24 (FILE* F)
99/* Read a 24 bit value from the file */
100{
101 unsigned long Lo = Read16 (F);
102 unsigned long Hi = Read8 (F);
103 return (Hi << 16) | Lo;
104}
105
106
107
108unsigned long Read32 (FILE* F)
109/* Read a 32 bit value from the file */
110{
111 unsigned long Lo = Read16 (F);
112 unsigned long Hi = Read16 (F);
113 return (Hi << 16) | Lo;
114}
115
116
117
118long Read32Signed (FILE* F)
119/* Read a 32 bit value from the file. Sign extend the value. */
120{
121 /* Read a 32 bit value */
122 unsigned long V = Read32 (F);
123
124 /* Sign extend the value */
125 if (V & 0x80000000UL) {
126 /* Signed value */
127 V |= ~0xFFFFFFFFUL;
128 }
129
130 /* Return it as a long */
131 return (long) V;
132}
133
134
135
136unsigned long ReadVar (FILE* F)
137/* Read a variable size value from the file */
138{
139 /* The value was written to the file in 7 bit chunks LSB first. If there
140 ** are more bytes, bit 8 is set, otherwise it is clear.
141 */
142 unsigned char C;
143 unsigned long V = 0;
144 unsigned Shift = 0;
145 do {
146 /* Read one byte */
147 C = Read8 (F);
148 /* Encode it into the target value */
149 V |= ((unsigned long)(C & 0x7F)) << Shift;
150 /* Next value */
151 Shift += 7;
152 } while (C & 0x80);
153
154 /* Return the value read */
155 return V;
156}
157
158
159
160char* ReadStr (FILE* F)
161/* Read a string from the file into a malloced area */
162{
163 /* Read the length */
164 unsigned Len = ReadVar (F);
165
166 /* Allocate memory */
167 char* Str = xmalloc (Len + 1);
168
169 /* Read the string itself */
170 ReadData (F, Str, Len);
171
172 /* Terminate the string and return it */
173 Str [Len] = '\0';
174 return Str;
175}
176
177
178
179FilePos* ReadFilePos (FILE* F, FilePos* Pos)
180/* Read a file position from the file */
181{
182 /* Read the data fields */
183 Pos->Line = ReadVar (F);
184 Pos->Col = ReadVar (F);
185 Pos->Name = ReadVar (F);
186 return Pos;
187}
188
189
190
191void* ReadData (FILE* F, void* Data, unsigned Size)
192/* Read data from the file */
193{
194 /* Accept zero sized reads */
195 if (Size > 0) {
196 if (fread (Data, 1, Size, F) != Size) {
197 Error ("Read error (file corrupt?)");
198 }
199 }
200 return Data;
201}
202
203
204
205void ReadObjHeader (FILE* F, ObjHeader* H)
206/* Read an object file header from the file */
207{
208 /* Read all fields */
209 H->Magic = Read32 (F);
210 H->Version = Read16 (F);
211 H->Flags = Read16 (F);
212 H->OptionOffs = Read32 (F);
213 H->OptionSize = Read32 (F);
214 H->FileOffs = Read32 (F);
215 H->FileSize = Read32 (F);
216 H->SegOffs = Read32 (F);
217 H->SegSize = Read32 (F);
218 H->ImportOffs = Read32 (F);
219 H->ImportSize = Read32 (F);
220 H->ExportOffs = Read32 (F);
221 H->ExportSize = Read32 (F);
222 H->DbgSymOffs = Read32 (F);
223 H->DbgSymSize = Read32 (F);
224 H->LineInfoOffs = Read32 (F);
225 H->LineInfoSize = Read32 (F);
226 H->StrPoolOffs = Read32 (F);
227 H->StrPoolSize = Read32 (F);
228 H->AssertOffs = Read32 (F);
229 H->AssertSize = Read32 (F);
230 H->ScopeOffs = Read32 (F);
231 H->ScopeSize = Read32 (F);
232 H->SpanOffs = Read32 (F);
233 H->SpanSize = Read32 (F);
234}
235
236
237
238void ReadStrPool (FILE* F, Collection* C)
239/* Read a string pool from the current position into C. */
240{
241 /* The number of strings is the first item */
242 unsigned long Count = ReadVar (F);
243
244 /* Read all the strings into C */
245 while (Count--) {
246 CollAppend (C, ReadStr (F));
247 }
248}
249