-
Notifications
You must be signed in to change notification settings - Fork 2
/
Copy pathfrag.c
209 lines (128 loc) · 5.01 KB
/
frag.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
/******************************************************************************
* @file frag.c
*****************************************************************************/
#include "frag.h"
#include "lib.h"
#include "section.h"
#include "types.h"
extern void get_filename_and_line_number (const char **filename_p, unsigned long *line_number_p);
struct frag zero_address_frag = { 0 };
frag_t current_frag;
struct frag *frag_alloc (void) {
struct frag *frag = xmalloc (sizeof (*frag));
return frag;
}
int frags_offset_is_fixed (const struct frag *frag1, const struct frag *frag2, offset_t *offset_p) {
const struct frag *frag;
offset_t offset;
offset = frag1->address - frag2->address;
if (frag1 == frag2) {
*offset_p = offset;
return 1;
}
/* Checks if frag2 is after frag1. */
frag = frag1;
while (frag->relax_type == RELAX_TYPE_NONE_NEEDED) {
offset += frag->fixed_size;
frag = frag->next;
if (frag == NULL) {
break;
}
if (frag == frag2) {
*offset_p = offset;
return 1;
}
}
/* Checks if frag1 is after frag2. */
offset = frag1->address - frag2->address;
frag = frag2;
while (frag->relax_type == RELAX_TYPE_NONE_NEEDED) {
offset -= frag->fixed_size;
frag = frag->next;
if (frag == NULL) {
break;
}
if (frag == frag1) {
*offset_p = offset;
return 1;
}
}
return 0;
}
int frags_is_greater_than_offset (value_t offset2, const struct frag *frag2, value_t offset1, const struct frag *frag1, offset_t *offset_p) {
offset_t difference;
const struct frag *frag;
/* Checks for something that should be impossible. */
if (frag2 == frag1 || offset1 > frag1->fixed_size) {
return 0;
}
difference = offset2 - offset1;
for (frag = frag1;;) {
difference += frag->fixed_size;
frag = frag->next;
if (frag == frag2) {
if (difference == 0) {
return 0;
}
break;
}
if (frag == NULL) {
return 0;
}
}
*offset_p = offset2 - offset1 - difference;
return 1;
}
unsigned char *frag_alloc_space (value_t space) {
if (current_frag->fixed_size + space >= current_frag->size) {
current_frag->size += ((space > FRAG_BUF_REALLOC_STEP) ? space : FRAG_BUF_REALLOC_STEP);
current_frag->buf = xrealloc (current_frag->buf, current_frag->size);
}
return current_frag->buf + current_frag->fixed_size;
}
unsigned char *frag_increase_fixed_size (value_t increase) {
frag_alloc_space (increase);
current_frag->fixed_size += increase;
return (current_frag->buf + current_frag->fixed_size - increase);
}
unsigned char *finished_frag_increase_fixed_size_by_frag_offset (struct frag *frag) {
frag->fixed_size += frag->offset;
if (frag->fixed_size > frag->size) {
frag->buf = xrealloc (frag->buf, frag->fixed_size);
frag->size = frag->fixed_size;
}
return (frag->buf + frag->fixed_size - frag->offset);
}
void frag_align (offset_t alignment, int fill_char, offset_t max_bytes_to_skip) {
(frag_alloc_space (1 << alignment))[0] = fill_char;
frag_set_as_variant (RELAX_TYPE_ALIGN, (relax_subtype_t) max_bytes_to_skip, NULL, alignment, 0, 0);
}
void frag_align_code (offset_t alignment, offset_t max_bytes_to_skip) {
(frag_alloc_space (1 << alignment))[0] = 0x90;
frag_set_as_variant (RELAX_TYPE_ALIGN_CODE, (relax_subtype_t) max_bytes_to_skip, NULL, alignment, 0, 0);
}
void frag_append_1_char (unsigned char ch) {
if (current_frag->fixed_size == current_frag->size) {
current_frag->size += FRAG_BUF_REALLOC_STEP;
current_frag->buf = xrealloc (current_frag->buf, current_frag->size);
}
current_frag->buf[current_frag->fixed_size++] = ch;
}
void frag_new (void) {
struct frag *prev_frag = current_frag;
current_frag = frag_alloc ();
current_frag->relax_type = RELAX_TYPE_NONE_NEEDED;
current_frag->next = NULL;
prev_frag->next = current_frag;
current_frag_chain->last_frag = current_frag;
}
void frag_set_as_variant (relax_type_t relax_type, relax_subtype_t relax_subtype, struct symbol *symbol, offset_t offset, value_t opcode_offset_in_buf, int far_call) {
current_frag->relax_type = relax_type;
current_frag->relax_subtype = relax_subtype;
current_frag->symbol = symbol;
current_frag->offset = offset;
current_frag->opcode_offset_in_buf = opcode_offset_in_buf;
if (far_call) { current_frag->far_call++; }
get_filename_and_line_number (&(current_frag->filename), &(current_frag->line_number));
frag_new ();
}