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@@ -1,430 +1,428 b'' | |||||
1 | /* |
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1 | /* | |
2 | mpatch.c - efficient binary patching for Mercurial |
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2 | mpatch.c - efficient binary patching for Mercurial | |
3 |
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3 | |||
4 | This implements a patch algorithm that's O(m + nlog n) where m is the |
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4 | This implements a patch algorithm that's O(m + nlog n) where m is the | |
5 | size of the output and n is the number of patches. |
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5 | size of the output and n is the number of patches. | |
6 |
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6 | |||
7 | Given a list of binary patches, it unpacks each into a hunk list, |
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7 | Given a list of binary patches, it unpacks each into a hunk list, | |
8 | then combines the hunk lists with a treewise recursion to form a |
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8 | then combines the hunk lists with a treewise recursion to form a | |
9 | single hunk list. This hunk list is then applied to the original |
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9 | single hunk list. This hunk list is then applied to the original | |
10 | text. |
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10 | text. | |
11 |
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11 | |||
12 | The text (or binary) fragments are copied directly from their source |
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12 | The text (or binary) fragments are copied directly from their source | |
13 | Python objects into a preallocated output string to avoid the |
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13 | Python objects into a preallocated output string to avoid the | |
14 | allocation of intermediate Python objects. Working memory is about 2x |
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14 | allocation of intermediate Python objects. Working memory is about 2x | |
15 | the total number of hunks. |
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15 | the total number of hunks. | |
16 |
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16 | |||
17 | Copyright 2005, 2006 Matt Mackall <mpm@selenic.com> |
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17 | Copyright 2005, 2006 Matt Mackall <mpm@selenic.com> | |
18 |
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18 | |||
19 | This software may be used and distributed according to the terms |
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19 | This software may be used and distributed according to the terms | |
20 | of the GNU General Public License, incorporated herein by reference. |
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20 | of the GNU General Public License, incorporated herein by reference. | |
21 | */ |
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21 | */ | |
22 |
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22 | |||
23 | #include <Python.h> |
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23 | #include <Python.h> | |
24 | #include <stdlib.h> |
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24 | #include <stdlib.h> | |
25 | #include <string.h> |
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25 | #include <string.h> | |
26 |
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26 | |||
27 | #include "util.h" |
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27 | #include "util.h" | |
28 |
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28 | |||
29 | static char mpatch_doc[] = "Efficient binary patching."; |
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29 | static char mpatch_doc[] = "Efficient binary patching."; | |
30 | static PyObject *mpatch_Error; |
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30 | static PyObject *mpatch_Error; | |
31 |
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31 | |||
32 | struct frag { |
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32 | struct frag { | |
33 | int start, end, len; |
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33 | int start, end, len; | |
34 | const char *data; |
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34 | const char *data; | |
35 | }; |
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35 | }; | |
36 |
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36 | |||
37 | struct flist { |
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37 | struct flist { | |
38 | struct frag *base, *head, *tail; |
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38 | struct frag *base, *head, *tail; | |
39 | }; |
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39 | }; | |
40 |
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40 | |||
41 |
static struct flist *lalloc( |
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41 | static struct flist *lalloc(Py_ssize_t size) | |
42 | { |
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42 | { | |
43 | struct flist *a = NULL; |
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43 | struct flist *a = NULL; | |
44 |
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44 | |||
45 | if (size < 1) |
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45 | if (size < 1) | |
46 | size = 1; |
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46 | size = 1; | |
47 |
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47 | |||
48 | a = (struct flist *)malloc(sizeof(struct flist)); |
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48 | a = (struct flist *)malloc(sizeof(struct flist)); | |
49 | if (a) { |
|
49 | if (a) { | |
50 | a->base = (struct frag *)malloc(sizeof(struct frag) * size); |
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50 | a->base = (struct frag *)malloc(sizeof(struct frag) * size); | |
51 | if (a->base) { |
|
51 | if (a->base) { | |
52 | a->head = a->tail = a->base; |
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52 | a->head = a->tail = a->base; | |
53 | return a; |
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53 | return a; | |
54 | } |
|
54 | } | |
55 | free(a); |
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55 | free(a); | |
56 | a = NULL; |
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56 | a = NULL; | |
57 | } |
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57 | } | |
58 | if (!PyErr_Occurred()) |
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58 | if (!PyErr_Occurred()) | |
59 | PyErr_NoMemory(); |
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59 | PyErr_NoMemory(); | |
60 | return NULL; |
|
60 | return NULL; | |
61 | } |
|
61 | } | |
62 |
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62 | |||
63 | static void lfree(struct flist *a) |
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63 | static void lfree(struct flist *a) | |
64 | { |
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64 | { | |
65 | if (a) { |
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65 | if (a) { | |
66 | free(a->base); |
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66 | free(a->base); | |
67 | free(a); |
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67 | free(a); | |
68 | } |
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68 | } | |
69 | } |
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69 | } | |
70 |
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70 | |||
71 |
static |
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71 | static Py_ssize_t lsize(struct flist *a) | |
72 | { |
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72 | { | |
73 | return a->tail - a->head; |
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73 | return a->tail - a->head; | |
74 | } |
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74 | } | |
75 |
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75 | |||
76 | /* move hunks in source that are less cut to dest, compensating |
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76 | /* move hunks in source that are less cut to dest, compensating | |
77 | for changes in offset. the last hunk may be split if necessary. |
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77 | for changes in offset. the last hunk may be split if necessary. | |
78 | */ |
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78 | */ | |
79 | static int gather(struct flist *dest, struct flist *src, int cut, int offset) |
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79 | static int gather(struct flist *dest, struct flist *src, int cut, int offset) | |
80 | { |
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80 | { | |
81 | struct frag *d = dest->tail, *s = src->head; |
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81 | struct frag *d = dest->tail, *s = src->head; | |
82 | int postend, c, l; |
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82 | int postend, c, l; | |
83 |
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83 | |||
84 | while (s != src->tail) { |
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84 | while (s != src->tail) { | |
85 | if (s->start + offset >= cut) |
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85 | if (s->start + offset >= cut) | |
86 | break; /* we've gone far enough */ |
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86 | break; /* we've gone far enough */ | |
87 |
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87 | |||
88 | postend = offset + s->start + s->len; |
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88 | postend = offset + s->start + s->len; | |
89 | if (postend <= cut) { |
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89 | if (postend <= cut) { | |
90 | /* save this hunk */ |
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90 | /* save this hunk */ | |
91 | offset += s->start + s->len - s->end; |
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91 | offset += s->start + s->len - s->end; | |
92 | *d++ = *s++; |
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92 | *d++ = *s++; | |
93 | } |
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93 | } | |
94 | else { |
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94 | else { | |
95 | /* break up this hunk */ |
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95 | /* break up this hunk */ | |
96 | c = cut - offset; |
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96 | c = cut - offset; | |
97 | if (s->end < c) |
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97 | if (s->end < c) | |
98 | c = s->end; |
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98 | c = s->end; | |
99 | l = cut - offset - s->start; |
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99 | l = cut - offset - s->start; | |
100 | if (s->len < l) |
|
100 | if (s->len < l) | |
101 | l = s->len; |
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101 | l = s->len; | |
102 |
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102 | |||
103 | offset += s->start + l - c; |
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103 | offset += s->start + l - c; | |
104 |
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104 | |||
105 | d->start = s->start; |
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105 | d->start = s->start; | |
106 | d->end = c; |
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106 | d->end = c; | |
107 | d->len = l; |
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107 | d->len = l; | |
108 | d->data = s->data; |
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108 | d->data = s->data; | |
109 | d++; |
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109 | d++; | |
110 | s->start = c; |
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110 | s->start = c; | |
111 | s->len = s->len - l; |
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111 | s->len = s->len - l; | |
112 | s->data = s->data + l; |
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112 | s->data = s->data + l; | |
113 |
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113 | |||
114 | break; |
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114 | break; | |
115 | } |
|
115 | } | |
116 | } |
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116 | } | |
117 |
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117 | |||
118 | dest->tail = d; |
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118 | dest->tail = d; | |
119 | src->head = s; |
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119 | src->head = s; | |
120 | return offset; |
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120 | return offset; | |
121 | } |
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121 | } | |
122 |
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122 | |||
123 | /* like gather, but with no output list */ |
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123 | /* like gather, but with no output list */ | |
124 | static int discard(struct flist *src, int cut, int offset) |
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124 | static int discard(struct flist *src, int cut, int offset) | |
125 | { |
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125 | { | |
126 | struct frag *s = src->head; |
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126 | struct frag *s = src->head; | |
127 | int postend, c, l; |
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127 | int postend, c, l; | |
128 |
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128 | |||
129 | while (s != src->tail) { |
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129 | while (s != src->tail) { | |
130 | if (s->start + offset >= cut) |
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130 | if (s->start + offset >= cut) | |
131 | break; |
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131 | break; | |
132 |
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132 | |||
133 | postend = offset + s->start + s->len; |
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133 | postend = offset + s->start + s->len; | |
134 | if (postend <= cut) { |
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134 | if (postend <= cut) { | |
135 | offset += s->start + s->len - s->end; |
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135 | offset += s->start + s->len - s->end; | |
136 | s++; |
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136 | s++; | |
137 | } |
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137 | } | |
138 | else { |
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138 | else { | |
139 | c = cut - offset; |
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139 | c = cut - offset; | |
140 | if (s->end < c) |
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140 | if (s->end < c) | |
141 | c = s->end; |
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141 | c = s->end; | |
142 | l = cut - offset - s->start; |
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142 | l = cut - offset - s->start; | |
143 | if (s->len < l) |
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143 | if (s->len < l) | |
144 | l = s->len; |
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144 | l = s->len; | |
145 |
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145 | |||
146 | offset += s->start + l - c; |
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146 | offset += s->start + l - c; | |
147 | s->start = c; |
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147 | s->start = c; | |
148 | s->len = s->len - l; |
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148 | s->len = s->len - l; | |
149 | s->data = s->data + l; |
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149 | s->data = s->data + l; | |
150 |
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150 | |||
151 | break; |
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151 | break; | |
152 | } |
|
152 | } | |
153 | } |
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153 | } | |
154 |
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154 | |||
155 | src->head = s; |
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155 | src->head = s; | |
156 | return offset; |
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156 | return offset; | |
157 | } |
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157 | } | |
158 |
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158 | |||
159 | /* combine hunk lists a and b, while adjusting b for offset changes in a/ |
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159 | /* combine hunk lists a and b, while adjusting b for offset changes in a/ | |
160 | this deletes a and b and returns the resultant list. */ |
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160 | this deletes a and b and returns the resultant list. */ | |
161 | static struct flist *combine(struct flist *a, struct flist *b) |
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161 | static struct flist *combine(struct flist *a, struct flist *b) | |
162 | { |
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162 | { | |
163 | struct flist *c = NULL; |
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163 | struct flist *c = NULL; | |
164 | struct frag *bh, *ct; |
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164 | struct frag *bh, *ct; | |
165 | int offset = 0, post; |
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165 | int offset = 0, post; | |
166 |
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166 | |||
167 | if (a && b) |
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167 | if (a && b) | |
168 | c = lalloc((lsize(a) + lsize(b)) * 2); |
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168 | c = lalloc((lsize(a) + lsize(b)) * 2); | |
169 |
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169 | |||
170 | if (c) { |
|
170 | if (c) { | |
171 |
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171 | |||
172 | for (bh = b->head; bh != b->tail; bh++) { |
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172 | for (bh = b->head; bh != b->tail; bh++) { | |
173 | /* save old hunks */ |
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173 | /* save old hunks */ | |
174 | offset = gather(c, a, bh->start, offset); |
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174 | offset = gather(c, a, bh->start, offset); | |
175 |
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175 | |||
176 | /* discard replaced hunks */ |
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176 | /* discard replaced hunks */ | |
177 | post = discard(a, bh->end, offset); |
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177 | post = discard(a, bh->end, offset); | |
178 |
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178 | |||
179 | /* insert new hunk */ |
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179 | /* insert new hunk */ | |
180 | ct = c->tail; |
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180 | ct = c->tail; | |
181 | ct->start = bh->start - offset; |
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181 | ct->start = bh->start - offset; | |
182 | ct->end = bh->end - post; |
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182 | ct->end = bh->end - post; | |
183 | ct->len = bh->len; |
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183 | ct->len = bh->len; | |
184 | ct->data = bh->data; |
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184 | ct->data = bh->data; | |
185 | c->tail++; |
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185 | c->tail++; | |
186 | offset = post; |
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186 | offset = post; | |
187 | } |
|
187 | } | |
188 |
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188 | |||
189 | /* hold on to tail from a */ |
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189 | /* hold on to tail from a */ | |
190 | memcpy(c->tail, a->head, sizeof(struct frag) * lsize(a)); |
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190 | memcpy(c->tail, a->head, sizeof(struct frag) * lsize(a)); | |
191 | c->tail += lsize(a); |
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191 | c->tail += lsize(a); | |
192 | } |
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192 | } | |
193 |
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193 | |||
194 | lfree(a); |
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194 | lfree(a); | |
195 | lfree(b); |
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195 | lfree(b); | |
196 | return c; |
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196 | return c; | |
197 | } |
|
197 | } | |
198 |
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198 | |||
199 | /* decode a binary patch into a hunk list */ |
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199 | /* decode a binary patch into a hunk list */ | |
200 |
static struct flist *decode(const char *bin, |
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200 | static struct flist *decode(const char *bin, Py_ssize_t len) | |
201 | { |
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201 | { | |
202 | struct flist *l; |
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202 | struct flist *l; | |
203 | struct frag *lt; |
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203 | struct frag *lt; | |
204 | const char *data = bin + 12, *end = bin + len; |
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204 | const char *data = bin + 12, *end = bin + len; | |
205 |
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205 | |||
206 | /* assume worst case size, we won't have many of these lists */ |
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206 | /* assume worst case size, we won't have many of these lists */ | |
207 | l = lalloc(len / 12); |
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207 | l = lalloc(len / 12); | |
208 | if (!l) |
|
208 | if (!l) | |
209 | return NULL; |
|
209 | return NULL; | |
210 |
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210 | |||
211 | lt = l->tail; |
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211 | lt = l->tail; | |
212 |
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212 | |||
213 | while (data <= end) { |
|
213 | while (data <= end) { | |
214 | lt->start = getbe32(bin); |
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214 | lt->start = getbe32(bin); | |
215 | lt->end = getbe32(bin + 4); |
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215 | lt->end = getbe32(bin + 4); | |
216 | lt->len = getbe32(bin + 8); |
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216 | lt->len = getbe32(bin + 8); | |
217 | if (lt->start > lt->end) |
|
217 | if (lt->start > lt->end) | |
218 | break; /* sanity check */ |
|
218 | break; /* sanity check */ | |
219 | bin = data + lt->len; |
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219 | bin = data + lt->len; | |
220 | if (bin < data) |
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220 | if (bin < data) | |
221 | break; /* big data + big (bogus) len can wrap around */ |
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221 | break; /* big data + big (bogus) len can wrap around */ | |
222 | lt->data = data; |
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222 | lt->data = data; | |
223 | data = bin + 12; |
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223 | data = bin + 12; | |
224 | lt++; |
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224 | lt++; | |
225 | } |
|
225 | } | |
226 |
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226 | |||
227 | if (bin != end) { |
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227 | if (bin != end) { | |
228 | if (!PyErr_Occurred()) |
|
228 | if (!PyErr_Occurred()) | |
229 | PyErr_SetString(mpatch_Error, "patch cannot be decoded"); |
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229 | PyErr_SetString(mpatch_Error, "patch cannot be decoded"); | |
230 | lfree(l); |
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230 | lfree(l); | |
231 | return NULL; |
|
231 | return NULL; | |
232 | } |
|
232 | } | |
233 |
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233 | |||
234 | l->tail = lt; |
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234 | l->tail = lt; | |
235 | return l; |
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235 | return l; | |
236 | } |
|
236 | } | |
237 |
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237 | |||
238 | /* calculate the size of resultant text */ |
|
238 | /* calculate the size of resultant text */ | |
239 |
static |
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239 | static Py_ssize_t calcsize(Py_ssize_t len, struct flist *l) | |
240 | { |
|
240 | { | |
241 |
|
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241 | Py_ssize_t outlen = 0, last = 0; | |
242 | struct frag *f = l->head; |
|
242 | struct frag *f = l->head; | |
243 |
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243 | |||
244 | while (f != l->tail) { |
|
244 | while (f != l->tail) { | |
245 | if (f->start < last || f->end > len) { |
|
245 | if (f->start < last || f->end > len) { | |
246 | if (!PyErr_Occurred()) |
|
246 | if (!PyErr_Occurred()) | |
247 | PyErr_SetString(mpatch_Error, |
|
247 | PyErr_SetString(mpatch_Error, | |
248 | "invalid patch"); |
|
248 | "invalid patch"); | |
249 | return -1; |
|
249 | return -1; | |
250 | } |
|
250 | } | |
251 | outlen += f->start - last; |
|
251 | outlen += f->start - last; | |
252 | last = f->end; |
|
252 | last = f->end; | |
253 | outlen += f->len; |
|
253 | outlen += f->len; | |
254 | f++; |
|
254 | f++; | |
255 | } |
|
255 | } | |
256 |
|
256 | |||
257 | outlen += len - last; |
|
257 | outlen += len - last; | |
258 | return outlen; |
|
258 | return outlen; | |
259 | } |
|
259 | } | |
260 |
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260 | |||
261 |
static int apply(char *buf, const char *orig, |
|
261 | static int apply(char *buf, const char *orig, Py_ssize_t len, struct flist *l) | |
262 | { |
|
262 | { | |
263 | struct frag *f = l->head; |
|
263 | struct frag *f = l->head; | |
264 | int last = 0; |
|
264 | int last = 0; | |
265 | char *p = buf; |
|
265 | char *p = buf; | |
266 |
|
266 | |||
267 | while (f != l->tail) { |
|
267 | while (f != l->tail) { | |
268 | if (f->start < last || f->end > len) { |
|
268 | if (f->start < last || f->end > len) { | |
269 | if (!PyErr_Occurred()) |
|
269 | if (!PyErr_Occurred()) | |
270 | PyErr_SetString(mpatch_Error, |
|
270 | PyErr_SetString(mpatch_Error, | |
271 | "invalid patch"); |
|
271 | "invalid patch"); | |
272 | return 0; |
|
272 | return 0; | |
273 | } |
|
273 | } | |
274 | memcpy(p, orig + last, f->start - last); |
|
274 | memcpy(p, orig + last, f->start - last); | |
275 | p += f->start - last; |
|
275 | p += f->start - last; | |
276 | memcpy(p, f->data, f->len); |
|
276 | memcpy(p, f->data, f->len); | |
277 | last = f->end; |
|
277 | last = f->end; | |
278 | p += f->len; |
|
278 | p += f->len; | |
279 | f++; |
|
279 | f++; | |
280 | } |
|
280 | } | |
281 | memcpy(p, orig + last, len - last); |
|
281 | memcpy(p, orig + last, len - last); | |
282 | return 1; |
|
282 | return 1; | |
283 | } |
|
283 | } | |
284 |
|
284 | |||
285 | /* recursively generate a patch of all bins between start and end */ |
|
285 | /* recursively generate a patch of all bins between start and end */ | |
286 |
static struct flist *fold(PyObject *bins, |
|
286 | static struct flist *fold(PyObject *bins, Py_ssize_t start, Py_ssize_t end) | |
287 | { |
|
287 | { | |
288 | int len; |
|
288 | Py_ssize_t len, blen; | |
289 | Py_ssize_t blen; |
|
|||
290 | const char *buffer; |
|
289 | const char *buffer; | |
291 |
|
290 | |||
292 | if (start + 1 == end) { |
|
291 | if (start + 1 == end) { | |
293 | /* trivial case, output a decoded list */ |
|
292 | /* trivial case, output a decoded list */ | |
294 | PyObject *tmp = PyList_GetItem(bins, start); |
|
293 | PyObject *tmp = PyList_GetItem(bins, start); | |
295 | if (!tmp) |
|
294 | if (!tmp) | |
296 | return NULL; |
|
295 | return NULL; | |
297 | if (PyObject_AsCharBuffer(tmp, &buffer, &blen)) |
|
296 | if (PyObject_AsCharBuffer(tmp, &buffer, &blen)) | |
298 | return NULL; |
|
297 | return NULL; | |
299 | return decode(buffer, blen); |
|
298 | return decode(buffer, blen); | |
300 | } |
|
299 | } | |
301 |
|
300 | |||
302 | /* divide and conquer, memory management is elsewhere */ |
|
301 | /* divide and conquer, memory management is elsewhere */ | |
303 | len = (end - start) / 2; |
|
302 | len = (end - start) / 2; | |
304 | return combine(fold(bins, start, start + len), |
|
303 | return combine(fold(bins, start, start + len), | |
305 | fold(bins, start + len, end)); |
|
304 | fold(bins, start + len, end)); | |
306 | } |
|
305 | } | |
307 |
|
306 | |||
308 | static PyObject * |
|
307 | static PyObject * | |
309 | patches(PyObject *self, PyObject *args) |
|
308 | patches(PyObject *self, PyObject *args) | |
310 | { |
|
309 | { | |
311 | PyObject *text, *bins, *result; |
|
310 | PyObject *text, *bins, *result; | |
312 | struct flist *patch; |
|
311 | struct flist *patch; | |
313 | const char *in; |
|
312 | const char *in; | |
314 | char *out; |
|
313 | char *out; | |
315 |
|
|
314 | Py_ssize_t len, outlen, inlen; | |
316 | Py_ssize_t inlen; |
|
|||
317 |
|
315 | |||
318 | if (!PyArg_ParseTuple(args, "OO:mpatch", &text, &bins)) |
|
316 | if (!PyArg_ParseTuple(args, "OO:mpatch", &text, &bins)) | |
319 | return NULL; |
|
317 | return NULL; | |
320 |
|
318 | |||
321 | len = PyList_Size(bins); |
|
319 | len = PyList_Size(bins); | |
322 | if (!len) { |
|
320 | if (!len) { | |
323 | /* nothing to do */ |
|
321 | /* nothing to do */ | |
324 | Py_INCREF(text); |
|
322 | Py_INCREF(text); | |
325 | return text; |
|
323 | return text; | |
326 | } |
|
324 | } | |
327 |
|
325 | |||
328 | if (PyObject_AsCharBuffer(text, &in, &inlen)) |
|
326 | if (PyObject_AsCharBuffer(text, &in, &inlen)) | |
329 | return NULL; |
|
327 | return NULL; | |
330 |
|
328 | |||
331 | patch = fold(bins, 0, len); |
|
329 | patch = fold(bins, 0, len); | |
332 | if (!patch) |
|
330 | if (!patch) | |
333 | return NULL; |
|
331 | return NULL; | |
334 |
|
332 | |||
335 | outlen = calcsize(inlen, patch); |
|
333 | outlen = calcsize(inlen, patch); | |
336 | if (outlen < 0) { |
|
334 | if (outlen < 0) { | |
337 | result = NULL; |
|
335 | result = NULL; | |
338 | goto cleanup; |
|
336 | goto cleanup; | |
339 | } |
|
337 | } | |
340 | result = PyBytes_FromStringAndSize(NULL, outlen); |
|
338 | result = PyBytes_FromStringAndSize(NULL, outlen); | |
341 | if (!result) { |
|
339 | if (!result) { | |
342 | result = NULL; |
|
340 | result = NULL; | |
343 | goto cleanup; |
|
341 | goto cleanup; | |
344 | } |
|
342 | } | |
345 | out = PyBytes_AsString(result); |
|
343 | out = PyBytes_AsString(result); | |
346 | if (!apply(out, in, inlen, patch)) { |
|
344 | if (!apply(out, in, inlen, patch)) { | |
347 | Py_DECREF(result); |
|
345 | Py_DECREF(result); | |
348 | result = NULL; |
|
346 | result = NULL; | |
349 | } |
|
347 | } | |
350 | cleanup: |
|
348 | cleanup: | |
351 | lfree(patch); |
|
349 | lfree(patch); | |
352 | return result; |
|
350 | return result; | |
353 | } |
|
351 | } | |
354 |
|
352 | |||
355 | /* calculate size of a patched file directly */ |
|
353 | /* calculate size of a patched file directly */ | |
356 | static PyObject * |
|
354 | static PyObject * | |
357 | patchedsize(PyObject *self, PyObject *args) |
|
355 | patchedsize(PyObject *self, PyObject *args) | |
358 | { |
|
356 | { | |
359 | long orig, start, end, len, outlen = 0, last = 0; |
|
357 | long orig, start, end, len, outlen = 0, last = 0; | |
360 | int patchlen; |
|
358 | int patchlen; | |
361 | char *bin, *binend, *data; |
|
359 | char *bin, *binend, *data; | |
362 |
|
360 | |||
363 | if (!PyArg_ParseTuple(args, "ls#", &orig, &bin, &patchlen)) |
|
361 | if (!PyArg_ParseTuple(args, "ls#", &orig, &bin, &patchlen)) | |
364 | return NULL; |
|
362 | return NULL; | |
365 |
|
363 | |||
366 | binend = bin + patchlen; |
|
364 | binend = bin + patchlen; | |
367 | data = bin + 12; |
|
365 | data = bin + 12; | |
368 |
|
366 | |||
369 | while (data <= binend) { |
|
367 | while (data <= binend) { | |
370 | start = getbe32(bin); |
|
368 | start = getbe32(bin); | |
371 | end = getbe32(bin + 4); |
|
369 | end = getbe32(bin + 4); | |
372 | len = getbe32(bin + 8); |
|
370 | len = getbe32(bin + 8); | |
373 | if (start > end) |
|
371 | if (start > end) | |
374 | break; /* sanity check */ |
|
372 | break; /* sanity check */ | |
375 | bin = data + len; |
|
373 | bin = data + len; | |
376 | if (bin < data) |
|
374 | if (bin < data) | |
377 | break; /* big data + big (bogus) len can wrap around */ |
|
375 | break; /* big data + big (bogus) len can wrap around */ | |
378 | data = bin + 12; |
|
376 | data = bin + 12; | |
379 | outlen += start - last; |
|
377 | outlen += start - last; | |
380 | last = end; |
|
378 | last = end; | |
381 | outlen += len; |
|
379 | outlen += len; | |
382 | } |
|
380 | } | |
383 |
|
381 | |||
384 | if (bin != binend) { |
|
382 | if (bin != binend) { | |
385 | if (!PyErr_Occurred()) |
|
383 | if (!PyErr_Occurred()) | |
386 | PyErr_SetString(mpatch_Error, "patch cannot be decoded"); |
|
384 | PyErr_SetString(mpatch_Error, "patch cannot be decoded"); | |
387 | return NULL; |
|
385 | return NULL; | |
388 | } |
|
386 | } | |
389 |
|
387 | |||
390 | outlen += orig - last; |
|
388 | outlen += orig - last; | |
391 | return Py_BuildValue("l", outlen); |
|
389 | return Py_BuildValue("l", outlen); | |
392 | } |
|
390 | } | |
393 |
|
391 | |||
394 | static PyMethodDef methods[] = { |
|
392 | static PyMethodDef methods[] = { | |
395 | {"patches", patches, METH_VARARGS, "apply a series of patches\n"}, |
|
393 | {"patches", patches, METH_VARARGS, "apply a series of patches\n"}, | |
396 | {"patchedsize", patchedsize, METH_VARARGS, "calculed patched size\n"}, |
|
394 | {"patchedsize", patchedsize, METH_VARARGS, "calculed patched size\n"}, | |
397 | {NULL, NULL} |
|
395 | {NULL, NULL} | |
398 | }; |
|
396 | }; | |
399 |
|
397 | |||
400 | #ifdef IS_PY3K |
|
398 | #ifdef IS_PY3K | |
401 | static struct PyModuleDef mpatch_module = { |
|
399 | static struct PyModuleDef mpatch_module = { | |
402 | PyModuleDef_HEAD_INIT, |
|
400 | PyModuleDef_HEAD_INIT, | |
403 | "mpatch", |
|
401 | "mpatch", | |
404 | mpatch_doc, |
|
402 | mpatch_doc, | |
405 | -1, |
|
403 | -1, | |
406 | methods |
|
404 | methods | |
407 | }; |
|
405 | }; | |
408 |
|
406 | |||
409 | PyMODINIT_FUNC PyInit_mpatch(void) |
|
407 | PyMODINIT_FUNC PyInit_mpatch(void) | |
410 | { |
|
408 | { | |
411 | PyObject *m; |
|
409 | PyObject *m; | |
412 |
|
410 | |||
413 | m = PyModule_Create(&mpatch_module); |
|
411 | m = PyModule_Create(&mpatch_module); | |
414 | if (m == NULL) |
|
412 | if (m == NULL) | |
415 | return NULL; |
|
413 | return NULL; | |
416 |
|
414 | |||
417 | mpatch_Error = PyErr_NewException("mpatch.mpatchError", NULL, NULL); |
|
415 | mpatch_Error = PyErr_NewException("mpatch.mpatchError", NULL, NULL); | |
418 | Py_INCREF(mpatch_Error); |
|
416 | Py_INCREF(mpatch_Error); | |
419 | PyModule_AddObject(m, "mpatchError", mpatch_Error); |
|
417 | PyModule_AddObject(m, "mpatchError", mpatch_Error); | |
420 |
|
418 | |||
421 | return m; |
|
419 | return m; | |
422 | } |
|
420 | } | |
423 | #else |
|
421 | #else | |
424 | PyMODINIT_FUNC |
|
422 | PyMODINIT_FUNC | |
425 | initmpatch(void) |
|
423 | initmpatch(void) | |
426 | { |
|
424 | { | |
427 | Py_InitModule3("mpatch", methods, mpatch_doc); |
|
425 | Py_InitModule3("mpatch", methods, mpatch_doc); | |
428 | mpatch_Error = PyErr_NewException("mpatch.mpatchError", NULL, NULL); |
|
426 | mpatch_Error = PyErr_NewException("mpatch.mpatchError", NULL, NULL); | |
429 | } |
|
427 | } | |
430 | #endif |
|
428 | #endif |
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