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@@ -1,360 +1,361 | |||||
1 | /* |
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1 | /* | |
2 | bdiff.c - efficient binary diff extension for Mercurial |
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2 | bdiff.c - efficient binary diff extension for Mercurial | |
3 |
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3 | |||
4 | Copyright 2005 Matt Mackall <mpm@selenic.com> |
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4 | Copyright 2005 Matt Mackall <mpm@selenic.com> | |
5 |
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5 | |||
6 | This software may be used and distributed according to the terms of |
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6 | This software may be used and distributed according to the terms of | |
7 | the GNU General Public License, incorporated herein by reference. |
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7 | the GNU General Public License, incorporated herein by reference. | |
8 |
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8 | |||
9 | Based roughly on Python difflib |
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9 | Based roughly on Python difflib | |
10 | */ |
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10 | */ | |
11 |
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11 | |||
12 | #include <Python.h> |
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12 | #include <Python.h> | |
13 | #include <stdlib.h> |
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13 | #include <stdlib.h> | |
14 | #include <string.h> |
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14 | #include <string.h> | |
15 |
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15 | |||
16 | #ifdef __hpux |
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16 | #ifdef __hpux | |
17 | #define inline |
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17 | #define inline | |
18 | #endif |
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18 | #endif | |
19 |
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19 | |||
20 | #ifdef __SUNPRO_C |
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20 | #ifdef __SUNPRO_C | |
21 | # define inline |
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21 | # define inline | |
22 | #endif |
|
22 | #endif | |
23 |
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23 | |||
24 | #ifdef _WIN32 |
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24 | #ifdef _WIN32 | |
25 | #ifdef _MSC_VER |
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25 | #ifdef _MSC_VER | |
26 | #define inline __inline |
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26 | #define inline __inline | |
27 | typedef unsigned long uint32_t; |
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27 | typedef unsigned long uint32_t; | |
28 | #else |
|
28 | #else | |
29 | #include <stdint.h> |
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29 | #include <stdint.h> | |
30 | #endif |
|
30 | #endif | |
31 | static uint32_t htonl(uint32_t x) |
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31 | static uint32_t htonl(uint32_t x) | |
32 | { |
|
32 | { | |
33 | return ((x & 0x000000ffUL) << 24) | |
|
33 | return ((x & 0x000000ffUL) << 24) | | |
34 | ((x & 0x0000ff00UL) << 8) | |
|
34 | ((x & 0x0000ff00UL) << 8) | | |
35 | ((x & 0x00ff0000UL) >> 8) | |
|
35 | ((x & 0x00ff0000UL) >> 8) | | |
36 | ((x & 0xff000000UL) >> 24); |
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36 | ((x & 0xff000000UL) >> 24); | |
37 | } |
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37 | } | |
38 | #else |
|
38 | #else | |
39 | #include <sys/types.h> |
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39 | #include <sys/types.h> | |
40 | #include <arpa/inet.h> |
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40 | #include <arpa/inet.h> | |
41 | #endif |
|
41 | #endif | |
42 |
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42 | |||
43 | struct line { |
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43 | struct line { | |
44 | int h, len, n, e; |
|
44 | int h, len, n, e; | |
45 | const char *l; |
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45 | const char *l; | |
46 | }; |
|
46 | }; | |
47 |
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47 | |||
48 | struct pos { |
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48 | struct pos { | |
49 | int pos, len; |
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49 | int pos, len; | |
50 | }; |
|
50 | }; | |
51 |
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51 | |||
52 | struct hunk { |
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52 | struct hunk { | |
53 | int a1, a2, b1, b2; |
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53 | int a1, a2, b1, b2; | |
54 | }; |
|
54 | }; | |
55 |
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55 | |||
56 | struct hunklist { |
|
56 | struct hunklist { | |
57 | struct hunk *base, *head; |
|
57 | struct hunk *base, *head; | |
58 | }; |
|
58 | }; | |
59 |
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59 | |||
60 | static inline uint32_t rol32(uint32_t word, unsigned int shift) |
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60 | static inline uint32_t rol32(uint32_t word, unsigned int shift) | |
61 | { |
|
61 | { | |
62 | return (word << shift) | (word >> (32 - shift)); |
|
62 | return (word << shift) | (word >> (32 - shift)); | |
63 | } |
|
63 | } | |
64 |
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64 | |||
65 | int splitlines(const char *a, int len, struct line **lr) |
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65 | int splitlines(const char *a, int len, struct line **lr) | |
66 | { |
|
66 | { | |
67 | int h, i; |
|
67 | int h, i; | |
68 | const char *p, *b = a; |
|
68 | const char *p, *b = a; | |
69 | struct line *l; |
|
69 | struct line *l; | |
70 |
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70 | |||
71 | /* count the lines */ |
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71 | /* count the lines */ | |
72 | i = 1; /* extra line for sentinel */ |
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72 | i = 1; /* extra line for sentinel */ | |
73 | for (p = a; p < a + len; p++) |
|
73 | for (p = a; p < a + len; p++) | |
74 | if (*p == '\n' || p == a + len - 1) |
|
74 | if (*p == '\n' || p == a + len - 1) | |
75 | i++; |
|
75 | i++; | |
76 |
|
76 | |||
77 | *lr = l = malloc(sizeof(struct line) * i); |
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77 | *lr = l = (struct line *)malloc(sizeof(struct line) * i); | |
78 | if (!l) |
|
78 | if (!l) | |
79 | return -1; |
|
79 | return -1; | |
80 |
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80 | |||
81 | /* build the line array and calculate hashes */ |
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81 | /* build the line array and calculate hashes */ | |
82 | h = 0; |
|
82 | h = 0; | |
83 | for (p = a; p < a + len; p++) { |
|
83 | for (p = a; p < a + len; p++) { | |
84 | h = *p + rol32(h, 7); /* a simple hash from GNU diff */ |
|
84 | h = *p + rol32(h, 7); /* a simple hash from GNU diff */ | |
85 | if (*p == '\n' || p == a + len - 1) { |
|
85 | if (*p == '\n' || p == a + len - 1) { | |
86 | l->len = p - b + 1; |
|
86 | l->len = p - b + 1; | |
87 | l->h = h * l->len; |
|
87 | l->h = h * l->len; | |
88 | l->l = b; |
|
88 | l->l = b; | |
89 | l->n = -1; |
|
89 | l->n = -1; | |
90 | l++; |
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90 | l++; | |
91 | b = p + 1; |
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91 | b = p + 1; | |
92 | h = 0; |
|
92 | h = 0; | |
93 | } |
|
93 | } | |
94 | } |
|
94 | } | |
95 |
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95 | |||
96 | /* set up a sentinel */ |
|
96 | /* set up a sentinel */ | |
97 | l->h = l->len = 0; |
|
97 | l->h = l->len = 0; | |
98 | l->l = a + len; |
|
98 | l->l = a + len; | |
99 | return i - 1; |
|
99 | return i - 1; | |
100 | } |
|
100 | } | |
101 |
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101 | |||
102 | int inline cmp(struct line *a, struct line *b) |
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102 | int inline cmp(struct line *a, struct line *b) | |
103 | { |
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103 | { | |
104 | return a->h != b->h || a->len != b->len || memcmp(a->l, b->l, a->len); |
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104 | return a->h != b->h || a->len != b->len || memcmp(a->l, b->l, a->len); | |
105 | } |
|
105 | } | |
106 |
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106 | |||
107 | static int equatelines(struct line *a, int an, struct line *b, int bn) |
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107 | static int equatelines(struct line *a, int an, struct line *b, int bn) | |
108 | { |
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108 | { | |
109 | int i, j, buckets = 1, t; |
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109 | int i, j, buckets = 1, t; | |
110 | struct pos *h; |
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110 | struct pos *h; | |
111 |
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111 | |||
112 | /* build a hash table of the next highest power of 2 */ |
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112 | /* build a hash table of the next highest power of 2 */ | |
113 | while (buckets < bn + 1) |
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113 | while (buckets < bn + 1) | |
114 | buckets *= 2; |
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114 | buckets *= 2; | |
115 |
|
115 | |||
116 | h = malloc(buckets * sizeof(struct pos)); |
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116 | h = (struct pos *)malloc(buckets * sizeof(struct pos)); | |
117 | buckets = buckets - 1; |
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117 | buckets = buckets - 1; | |
118 | if (!h) |
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118 | if (!h) | |
119 | return 0; |
|
119 | return 0; | |
120 |
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120 | |||
121 | /* clear the hash table */ |
|
121 | /* clear the hash table */ | |
122 | for (i = 0; i <= buckets; i++) { |
|
122 | for (i = 0; i <= buckets; i++) { | |
123 | h[i].pos = -1; |
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123 | h[i].pos = -1; | |
124 | h[i].len = 0; |
|
124 | h[i].len = 0; | |
125 | } |
|
125 | } | |
126 |
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126 | |||
127 | /* add lines to the hash table chains */ |
|
127 | /* add lines to the hash table chains */ | |
128 | for (i = bn - 1; i >= 0; i--) { |
|
128 | for (i = bn - 1; i >= 0; i--) { | |
129 | /* find the equivalence class */ |
|
129 | /* find the equivalence class */ | |
130 | for (j = b[i].h & buckets; h[j].pos != -1; |
|
130 | for (j = b[i].h & buckets; h[j].pos != -1; | |
131 | j = (j + 1) & buckets) |
|
131 | j = (j + 1) & buckets) | |
132 | if (!cmp(b + i, b + h[j].pos)) |
|
132 | if (!cmp(b + i, b + h[j].pos)) | |
133 | break; |
|
133 | break; | |
134 |
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134 | |||
135 | /* add to the head of the equivalence class */ |
|
135 | /* add to the head of the equivalence class */ | |
136 | b[i].n = h[j].pos; |
|
136 | b[i].n = h[j].pos; | |
137 | b[i].e = j; |
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137 | b[i].e = j; | |
138 | h[j].pos = i; |
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138 | h[j].pos = i; | |
139 | h[j].len++; /* keep track of popularity */ |
|
139 | h[j].len++; /* keep track of popularity */ | |
140 | } |
|
140 | } | |
141 |
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141 | |||
142 | /* compute popularity threshold */ |
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142 | /* compute popularity threshold */ | |
143 | t = (bn >= 200) ? bn / 100 : bn + 1; |
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143 | t = (bn >= 200) ? bn / 100 : bn + 1; | |
144 |
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144 | |||
145 | /* match items in a to their equivalence class in b */ |
|
145 | /* match items in a to their equivalence class in b */ | |
146 | for (i = 0; i < an; i++) { |
|
146 | for (i = 0; i < an; i++) { | |
147 | /* find the equivalence class */ |
|
147 | /* find the equivalence class */ | |
148 | for (j = a[i].h & buckets; h[j].pos != -1; |
|
148 | for (j = a[i].h & buckets; h[j].pos != -1; | |
149 | j = (j + 1) & buckets) |
|
149 | j = (j + 1) & buckets) | |
150 | if (!cmp(a + i, b + h[j].pos)) |
|
150 | if (!cmp(a + i, b + h[j].pos)) | |
151 | break; |
|
151 | break; | |
152 |
|
152 | |||
153 | a[i].e = j; /* use equivalence class for quick compare */ |
|
153 | a[i].e = j; /* use equivalence class for quick compare */ | |
154 | if (h[j].len <= t) |
|
154 | if (h[j].len <= t) | |
155 | a[i].n = h[j].pos; /* point to head of match list */ |
|
155 | a[i].n = h[j].pos; /* point to head of match list */ | |
156 | else |
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156 | else | |
157 | a[i].n = -1; /* too popular */ |
|
157 | a[i].n = -1; /* too popular */ | |
158 | } |
|
158 | } | |
159 |
|
159 | |||
160 | /* discard hash tables */ |
|
160 | /* discard hash tables */ | |
161 | free(h); |
|
161 | free(h); | |
162 | return 1; |
|
162 | return 1; | |
163 | } |
|
163 | } | |
164 |
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164 | |||
165 | static int longest_match(struct line *a, struct line *b, struct pos *pos, |
|
165 | static int longest_match(struct line *a, struct line *b, struct pos *pos, | |
166 | int a1, int a2, int b1, int b2, int *omi, int *omj) |
|
166 | int a1, int a2, int b1, int b2, int *omi, int *omj) | |
167 | { |
|
167 | { | |
168 | int mi = a1, mj = b1, mk = 0, mb = 0, i, j, k; |
|
168 | int mi = a1, mj = b1, mk = 0, mb = 0, i, j, k; | |
169 |
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169 | |||
170 | for (i = a1; i < a2; i++) { |
|
170 | for (i = a1; i < a2; i++) { | |
171 | /* skip things before the current block */ |
|
171 | /* skip things before the current block */ | |
172 | for (j = a[i].n; j != -1 && j < b1; j = b[j].n) |
|
172 | for (j = a[i].n; j != -1 && j < b1; j = b[j].n) | |
173 | ; |
|
173 | ; | |
174 |
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174 | |||
175 | /* loop through all lines match a[i] in b */ |
|
175 | /* loop through all lines match a[i] in b */ | |
176 | for (; j != -1 && j < b2; j = b[j].n) { |
|
176 | for (; j != -1 && j < b2; j = b[j].n) { | |
177 | /* does this extend an earlier match? */ |
|
177 | /* does this extend an earlier match? */ | |
178 | if (i > a1 && j > b1 && pos[j - 1].pos == i - 1) |
|
178 | if (i > a1 && j > b1 && pos[j - 1].pos == i - 1) | |
179 | k = pos[j - 1].len + 1; |
|
179 | k = pos[j - 1].len + 1; | |
180 | else |
|
180 | else | |
181 | k = 1; |
|
181 | k = 1; | |
182 | pos[j].pos = i; |
|
182 | pos[j].pos = i; | |
183 | pos[j].len = k; |
|
183 | pos[j].len = k; | |
184 |
|
184 | |||
185 | /* best match so far? */ |
|
185 | /* best match so far? */ | |
186 | if (k > mk) { |
|
186 | if (k > mk) { | |
187 | mi = i; |
|
187 | mi = i; | |
188 | mj = j; |
|
188 | mj = j; | |
189 | mk = k; |
|
189 | mk = k; | |
190 | } |
|
190 | } | |
191 | } |
|
191 | } | |
192 | } |
|
192 | } | |
193 |
|
193 | |||
194 | if (mk) { |
|
194 | if (mk) { | |
195 | mi = mi - mk + 1; |
|
195 | mi = mi - mk + 1; | |
196 | mj = mj - mk + 1; |
|
196 | mj = mj - mk + 1; | |
197 | } |
|
197 | } | |
198 |
|
198 | |||
199 | /* expand match to include neighboring popular lines */ |
|
199 | /* expand match to include neighboring popular lines */ | |
200 | while (mi - mb > a1 && mj - mb > b1 && |
|
200 | while (mi - mb > a1 && mj - mb > b1 && | |
201 | a[mi - mb - 1].e == b[mj - mb - 1].e) |
|
201 | a[mi - mb - 1].e == b[mj - mb - 1].e) | |
202 | mb++; |
|
202 | mb++; | |
203 | while (mi + mk < a2 && mj + mk < b2 && |
|
203 | while (mi + mk < a2 && mj + mk < b2 && | |
204 | a[mi + mk].e == b[mj + mk].e) |
|
204 | a[mi + mk].e == b[mj + mk].e) | |
205 | mk++; |
|
205 | mk++; | |
206 |
|
206 | |||
207 | *omi = mi - mb; |
|
207 | *omi = mi - mb; | |
208 | *omj = mj - mb; |
|
208 | *omj = mj - mb; | |
209 | return mk + mb; |
|
209 | return mk + mb; | |
210 | } |
|
210 | } | |
211 |
|
211 | |||
212 | static void recurse(struct line *a, struct line *b, struct pos *pos, |
|
212 | static void recurse(struct line *a, struct line *b, struct pos *pos, | |
213 | int a1, int a2, int b1, int b2, struct hunklist *l) |
|
213 | int a1, int a2, int b1, int b2, struct hunklist *l) | |
214 | { |
|
214 | { | |
215 | int i, j, k; |
|
215 | int i, j, k; | |
216 |
|
216 | |||
217 | /* find the longest match in this chunk */ |
|
217 | /* find the longest match in this chunk */ | |
218 | k = longest_match(a, b, pos, a1, a2, b1, b2, &i, &j); |
|
218 | k = longest_match(a, b, pos, a1, a2, b1, b2, &i, &j); | |
219 | if (!k) |
|
219 | if (!k) | |
220 | return; |
|
220 | return; | |
221 |
|
221 | |||
222 | /* and recurse on the remaining chunks on either side */ |
|
222 | /* and recurse on the remaining chunks on either side */ | |
223 | recurse(a, b, pos, a1, i, b1, j, l); |
|
223 | recurse(a, b, pos, a1, i, b1, j, l); | |
224 | l->head->a1 = i; |
|
224 | l->head->a1 = i; | |
225 | l->head->a2 = i + k; |
|
225 | l->head->a2 = i + k; | |
226 | l->head->b1 = j; |
|
226 | l->head->b1 = j; | |
227 | l->head->b2 = j + k; |
|
227 | l->head->b2 = j + k; | |
228 | l->head++; |
|
228 | l->head++; | |
229 | recurse(a, b, pos, i + k, a2, j + k, b2, l); |
|
229 | recurse(a, b, pos, i + k, a2, j + k, b2, l); | |
230 | } |
|
230 | } | |
231 |
|
231 | |||
232 | static struct hunklist diff(struct line *a, int an, struct line *b, int bn) |
|
232 | static struct hunklist diff(struct line *a, int an, struct line *b, int bn) | |
233 | { |
|
233 | { | |
234 | struct hunklist l; |
|
234 | struct hunklist l; | |
235 | struct pos *pos; |
|
235 | struct pos *pos; | |
236 | int t; |
|
236 | int t; | |
237 |
|
237 | |||
238 | /* allocate and fill arrays */ |
|
238 | /* allocate and fill arrays */ | |
239 | t = equatelines(a, an, b, bn); |
|
239 | t = equatelines(a, an, b, bn); | |
240 | pos = calloc(bn, sizeof(struct pos)); |
|
240 | pos = (struct pos *)calloc(bn, sizeof(struct pos)); | |
241 | /* we can't have more matches than lines in the shorter file */ |
|
241 | /* we can't have more matches than lines in the shorter file */ | |
242 |
l.head = l.base = malloc(sizeof(struct hunk) * |
|
242 | l.head = l.base = (struct hunk *)malloc(sizeof(struct hunk) * | |
|
243 | ((an<bn ? an:bn) + 1)); | |||
243 |
|
244 | |||
244 | if (pos && l.base && t) { |
|
245 | if (pos && l.base && t) { | |
245 | /* generate the matching block list */ |
|
246 | /* generate the matching block list */ | |
246 | recurse(a, b, pos, 0, an, 0, bn, &l); |
|
247 | recurse(a, b, pos, 0, an, 0, bn, &l); | |
247 | l.head->a1 = an; |
|
248 | l.head->a1 = an; | |
248 | l.head->b1 = bn; |
|
249 | l.head->b1 = bn; | |
249 | l.head++; |
|
250 | l.head++; | |
250 | } |
|
251 | } | |
251 |
|
252 | |||
252 | free(pos); |
|
253 | free(pos); | |
253 | return l; |
|
254 | return l; | |
254 | } |
|
255 | } | |
255 |
|
256 | |||
256 | static PyObject *blocks(PyObject *self, PyObject *args) |
|
257 | static PyObject *blocks(PyObject *self, PyObject *args) | |
257 | { |
|
258 | { | |
258 | PyObject *sa, *sb, *rl = NULL, *m; |
|
259 | PyObject *sa, *sb, *rl = NULL, *m; | |
259 | struct line *a, *b; |
|
260 | struct line *a, *b; | |
260 | struct hunklist l = {NULL, NULL}; |
|
261 | struct hunklist l = {NULL, NULL}; | |
261 | struct hunk *h; |
|
262 | struct hunk *h; | |
262 | int an, bn, pos = 0; |
|
263 | int an, bn, pos = 0; | |
263 |
|
264 | |||
264 | if (!PyArg_ParseTuple(args, "SS:bdiff", &sa, &sb)) |
|
265 | if (!PyArg_ParseTuple(args, "SS:bdiff", &sa, &sb)) | |
265 | return NULL; |
|
266 | return NULL; | |
266 |
|
267 | |||
267 | an = splitlines(PyString_AsString(sa), PyString_Size(sa), &a); |
|
268 | an = splitlines(PyString_AsString(sa), PyString_Size(sa), &a); | |
268 | bn = splitlines(PyString_AsString(sb), PyString_Size(sb), &b); |
|
269 | bn = splitlines(PyString_AsString(sb), PyString_Size(sb), &b); | |
269 | if (!a || !b) |
|
270 | if (!a || !b) | |
270 | goto nomem; |
|
271 | goto nomem; | |
271 |
|
272 | |||
272 | l = diff(a, an, b, bn); |
|
273 | l = diff(a, an, b, bn); | |
273 | rl = PyList_New(l.head - l.base); |
|
274 | rl = PyList_New(l.head - l.base); | |
274 | if (!l.head || !rl) |
|
275 | if (!l.head || !rl) | |
275 | goto nomem; |
|
276 | goto nomem; | |
276 |
|
277 | |||
277 | for (h = l.base; h != l.head; h++) { |
|
278 | for (h = l.base; h != l.head; h++) { | |
278 | m = Py_BuildValue("iiii", h->a1, h->a2, h->b1, h->b2); |
|
279 | m = Py_BuildValue("iiii", h->a1, h->a2, h->b1, h->b2); | |
279 | PyList_SetItem(rl, pos, m); |
|
280 | PyList_SetItem(rl, pos, m); | |
280 | pos++; |
|
281 | pos++; | |
281 | } |
|
282 | } | |
282 |
|
283 | |||
283 | nomem: |
|
284 | nomem: | |
284 | free(a); |
|
285 | free(a); | |
285 | free(b); |
|
286 | free(b); | |
286 | free(l.base); |
|
287 | free(l.base); | |
287 | return rl ? rl : PyErr_NoMemory(); |
|
288 | return rl ? rl : PyErr_NoMemory(); | |
288 | } |
|
289 | } | |
289 |
|
290 | |||
290 | static PyObject *bdiff(PyObject *self, PyObject *args) |
|
291 | static PyObject *bdiff(PyObject *self, PyObject *args) | |
291 | { |
|
292 | { | |
292 | PyObject *sa, *sb, *result = NULL; |
|
293 | PyObject *sa, *sb, *result = NULL; | |
293 | struct line *al, *bl; |
|
294 | struct line *al, *bl; | |
294 | struct hunklist l = {NULL, NULL}; |
|
295 | struct hunklist l = {NULL, NULL}; | |
295 | struct hunk *h; |
|
296 | struct hunk *h; | |
296 | char encode[12], *rb; |
|
297 | char encode[12], *rb; | |
297 | int an, bn, len = 0, la = 0, lb = 0; |
|
298 | int an, bn, len = 0, la = 0, lb = 0; | |
298 |
|
299 | |||
299 | if (!PyArg_ParseTuple(args, "SS:bdiff", &sa, &sb)) |
|
300 | if (!PyArg_ParseTuple(args, "SS:bdiff", &sa, &sb)) | |
300 | return NULL; |
|
301 | return NULL; | |
301 |
|
302 | |||
302 | an = splitlines(PyString_AsString(sa), PyString_Size(sa), &al); |
|
303 | an = splitlines(PyString_AsString(sa), PyString_Size(sa), &al); | |
303 | bn = splitlines(PyString_AsString(sb), PyString_Size(sb), &bl); |
|
304 | bn = splitlines(PyString_AsString(sb), PyString_Size(sb), &bl); | |
304 | if (!al || !bl) |
|
305 | if (!al || !bl) | |
305 | goto nomem; |
|
306 | goto nomem; | |
306 |
|
307 | |||
307 | l = diff(al, an, bl, bn); |
|
308 | l = diff(al, an, bl, bn); | |
308 | if (!l.head) |
|
309 | if (!l.head) | |
309 | goto nomem; |
|
310 | goto nomem; | |
310 |
|
311 | |||
311 | /* calculate length of output */ |
|
312 | /* calculate length of output */ | |
312 | for (h = l.base; h != l.head; h++) { |
|
313 | for (h = l.base; h != l.head; h++) { | |
313 | if (h->a1 != la || h->b1 != lb) |
|
314 | if (h->a1 != la || h->b1 != lb) | |
314 | len += 12 + bl[h->b1].l - bl[lb].l; |
|
315 | len += 12 + bl[h->b1].l - bl[lb].l; | |
315 | la = h->a2; |
|
316 | la = h->a2; | |
316 | lb = h->b2; |
|
317 | lb = h->b2; | |
317 | } |
|
318 | } | |
318 |
|
319 | |||
319 | result = PyString_FromStringAndSize(NULL, len); |
|
320 | result = PyString_FromStringAndSize(NULL, len); | |
320 | if (!result) |
|
321 | if (!result) | |
321 | goto nomem; |
|
322 | goto nomem; | |
322 |
|
323 | |||
323 | /* build binary patch */ |
|
324 | /* build binary patch */ | |
324 | rb = PyString_AsString(result); |
|
325 | rb = PyString_AsString(result); | |
325 | la = lb = 0; |
|
326 | la = lb = 0; | |
326 |
|
327 | |||
327 | for (h = l.base; h != l.head; h++) { |
|
328 | for (h = l.base; h != l.head; h++) { | |
328 | if (h->a1 != la || h->b1 != lb) { |
|
329 | if (h->a1 != la || h->b1 != lb) { | |
329 | len = bl[h->b1].l - bl[lb].l; |
|
330 | len = bl[h->b1].l - bl[lb].l; | |
330 | *(uint32_t *)(encode) = htonl(al[la].l - al->l); |
|
331 | *(uint32_t *)(encode) = htonl(al[la].l - al->l); | |
331 | *(uint32_t *)(encode + 4) = htonl(al[h->a1].l - al->l); |
|
332 | *(uint32_t *)(encode + 4) = htonl(al[h->a1].l - al->l); | |
332 | *(uint32_t *)(encode + 8) = htonl(len); |
|
333 | *(uint32_t *)(encode + 8) = htonl(len); | |
333 | memcpy(rb, encode, 12); |
|
334 | memcpy(rb, encode, 12); | |
334 | memcpy(rb + 12, bl[lb].l, len); |
|
335 | memcpy(rb + 12, bl[lb].l, len); | |
335 | rb += 12 + len; |
|
336 | rb += 12 + len; | |
336 | } |
|
337 | } | |
337 | la = h->a2; |
|
338 | la = h->a2; | |
338 | lb = h->b2; |
|
339 | lb = h->b2; | |
339 | } |
|
340 | } | |
340 |
|
341 | |||
341 | nomem: |
|
342 | nomem: | |
342 | free(al); |
|
343 | free(al); | |
343 | free(bl); |
|
344 | free(bl); | |
344 | free(l.base); |
|
345 | free(l.base); | |
345 | return result ? result : PyErr_NoMemory(); |
|
346 | return result ? result : PyErr_NoMemory(); | |
346 | } |
|
347 | } | |
347 |
|
348 | |||
348 | static char mdiff_doc[] = "Efficient binary diff."; |
|
349 | static char mdiff_doc[] = "Efficient binary diff."; | |
349 |
|
350 | |||
350 | static PyMethodDef methods[] = { |
|
351 | static PyMethodDef methods[] = { | |
351 | {"bdiff", bdiff, METH_VARARGS, "calculate a binary diff\n"}, |
|
352 | {"bdiff", bdiff, METH_VARARGS, "calculate a binary diff\n"}, | |
352 | {"blocks", blocks, METH_VARARGS, "find a list of matching lines\n"}, |
|
353 | {"blocks", blocks, METH_VARARGS, "find a list of matching lines\n"}, | |
353 | {NULL, NULL} |
|
354 | {NULL, NULL} | |
354 | }; |
|
355 | }; | |
355 |
|
356 | |||
356 | PyMODINIT_FUNC initbdiff(void) |
|
357 | PyMODINIT_FUNC initbdiff(void) | |
357 | { |
|
358 | { | |
358 | Py_InitModule3("bdiff", methods, mdiff_doc); |
|
359 | Py_InitModule3("bdiff", methods, mdiff_doc); | |
359 | } |
|
360 | } | |
360 |
|
361 |
@@ -1,368 +1,368 | |||||
1 | /* |
|
1 | /* | |
2 | mpatch.c - efficient binary patching for Mercurial |
|
2 | mpatch.c - efficient binary patching for Mercurial | |
3 |
|
3 | |||
4 | This implements a patch algorithm that's O(m + nlog n) where m is the |
|
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. |
|
5 | size of the output and n is the number of patches. | |
6 |
|
6 | |||
7 | Given a list of binary patches, it unpacks each into a hunk list, |
|
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 |
|
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 |
|
9 | single hunk list. This hunk list is then applied to the original | |
10 | text. |
|
10 | text. | |
11 |
|
11 | |||
12 | The text (or binary) fragments are copied directly from their source |
|
12 | The text (or binary) fragments are copied directly from their source | |
13 | Python objects into a preallocated output string to avoid the |
|
13 | Python objects into a preallocated output string to avoid the | |
14 | allocation of intermediate Python objects. Working memory is about 2x |
|
14 | allocation of intermediate Python objects. Working memory is about 2x | |
15 | the total number of hunks. |
|
15 | the total number of hunks. | |
16 |
|
16 | |||
17 | Copyright 2005 Matt Mackall <mpm@selenic.com> |
|
17 | Copyright 2005 Matt Mackall <mpm@selenic.com> | |
18 |
|
18 | |||
19 | This software may be used and distributed according to the terms |
|
19 | This software may be used and distributed according to the terms | |
20 | of the GNU General Public License, incorporated herein by reference. |
|
20 | of the GNU General Public License, incorporated herein by reference. | |
21 | */ |
|
21 | */ | |
22 |
|
22 | |||
23 | #include <Python.h> |
|
23 | #include <Python.h> | |
24 | #include <stdlib.h> |
|
24 | #include <stdlib.h> | |
25 | #include <string.h> |
|
25 | #include <string.h> | |
26 | #ifdef _WIN32 |
|
26 | #ifdef _WIN32 | |
27 | #ifdef _MSC_VER |
|
27 | #ifdef _MSC_VER | |
28 | #define inline __inline |
|
28 | #define inline __inline | |
29 | typedef unsigned long uint32_t; |
|
29 | typedef unsigned long uint32_t; | |
30 | #else |
|
30 | #else | |
31 | #include <stdint.h> |
|
31 | #include <stdint.h> | |
32 | #endif |
|
32 | #endif | |
33 | static uint32_t ntohl(uint32_t x) |
|
33 | static uint32_t ntohl(uint32_t x) | |
34 | { |
|
34 | { | |
35 | return ((x & 0x000000ffUL) << 24) | |
|
35 | return ((x & 0x000000ffUL) << 24) | | |
36 | ((x & 0x0000ff00UL) << 8) | |
|
36 | ((x & 0x0000ff00UL) << 8) | | |
37 | ((x & 0x00ff0000UL) >> 8) | |
|
37 | ((x & 0x00ff0000UL) >> 8) | | |
38 | ((x & 0xff000000UL) >> 24); |
|
38 | ((x & 0xff000000UL) >> 24); | |
39 | } |
|
39 | } | |
40 | #else |
|
40 | #else | |
41 | #include <sys/types.h> |
|
41 | #include <sys/types.h> | |
42 | #include <arpa/inet.h> |
|
42 | #include <arpa/inet.h> | |
43 | #endif |
|
43 | #endif | |
44 |
|
44 | |||
45 | static char mpatch_doc[] = "Efficient binary patching."; |
|
45 | static char mpatch_doc[] = "Efficient binary patching."; | |
46 | static PyObject *mpatch_Error; |
|
46 | static PyObject *mpatch_Error; | |
47 |
|
47 | |||
48 | struct frag { |
|
48 | struct frag { | |
49 | int start, end, len; |
|
49 | int start, end, len; | |
50 | char *data; |
|
50 | char *data; | |
51 | }; |
|
51 | }; | |
52 |
|
52 | |||
53 | struct flist { |
|
53 | struct flist { | |
54 | struct frag *base, *head, *tail; |
|
54 | struct frag *base, *head, *tail; | |
55 | }; |
|
55 | }; | |
56 |
|
56 | |||
57 | static struct flist *lalloc(int size) |
|
57 | static struct flist *lalloc(int size) | |
58 | { |
|
58 | { | |
59 | struct flist *a = NULL; |
|
59 | struct flist *a = NULL; | |
60 |
|
60 | |||
61 | a = malloc(sizeof(struct flist)); |
|
61 | a = (struct flist *)malloc(sizeof(struct flist)); | |
62 | if (a) { |
|
62 | if (a) { | |
63 | a->base = malloc(sizeof(struct frag) * size); |
|
63 | a->base = (struct frag *)malloc(sizeof(struct frag) * size); | |
64 | if (!a->base) { |
|
64 | if (!a->base) { | |
65 | free(a); |
|
65 | free(a); | |
66 | a = NULL; |
|
66 | a = NULL; | |
67 | } else |
|
67 | } else | |
68 | a->head = a->tail = a->base; |
|
68 | a->head = a->tail = a->base; | |
69 | return a; |
|
69 | return a; | |
70 | } |
|
70 | } | |
71 | if (!PyErr_Occurred()) |
|
71 | if (!PyErr_Occurred()) | |
72 | PyErr_NoMemory(); |
|
72 | PyErr_NoMemory(); | |
73 | return NULL; |
|
73 | return NULL; | |
74 | } |
|
74 | } | |
75 |
|
75 | |||
76 | static void lfree(struct flist *a) |
|
76 | static void lfree(struct flist *a) | |
77 | { |
|
77 | { | |
78 | if (a) { |
|
78 | if (a) { | |
79 | free(a->base); |
|
79 | free(a->base); | |
80 | free(a); |
|
80 | free(a); | |
81 | } |
|
81 | } | |
82 | } |
|
82 | } | |
83 |
|
83 | |||
84 | static int lsize(struct flist *a) |
|
84 | static int lsize(struct flist *a) | |
85 | { |
|
85 | { | |
86 | return a->tail - a->head; |
|
86 | return a->tail - a->head; | |
87 | } |
|
87 | } | |
88 |
|
88 | |||
89 | /* move hunks in source that are less cut to dest, compensating |
|
89 | /* move hunks in source that are less cut to dest, compensating | |
90 | for changes in offset. the last hunk may be split if necessary. |
|
90 | for changes in offset. the last hunk may be split if necessary. | |
91 | */ |
|
91 | */ | |
92 | static int gather(struct flist *dest, struct flist *src, int cut, int offset) |
|
92 | static int gather(struct flist *dest, struct flist *src, int cut, int offset) | |
93 | { |
|
93 | { | |
94 | struct frag *d = dest->tail, *s = src->head; |
|
94 | struct frag *d = dest->tail, *s = src->head; | |
95 | int postend, c, l; |
|
95 | int postend, c, l; | |
96 |
|
96 | |||
97 | while (s != src->tail) { |
|
97 | while (s != src->tail) { | |
98 | if (s->start + offset >= cut) |
|
98 | if (s->start + offset >= cut) | |
99 | break; /* we've gone far enough */ |
|
99 | break; /* we've gone far enough */ | |
100 |
|
100 | |||
101 | postend = offset + s->start + s->len; |
|
101 | postend = offset + s->start + s->len; | |
102 | if (postend <= cut) { |
|
102 | if (postend <= cut) { | |
103 | /* save this hunk */ |
|
103 | /* save this hunk */ | |
104 | offset += s->start + s->len - s->end; |
|
104 | offset += s->start + s->len - s->end; | |
105 | *d++ = *s++; |
|
105 | *d++ = *s++; | |
106 | } |
|
106 | } | |
107 | else { |
|
107 | else { | |
108 | /* break up this hunk */ |
|
108 | /* break up this hunk */ | |
109 | c = cut - offset; |
|
109 | c = cut - offset; | |
110 | if (s->end < c) |
|
110 | if (s->end < c) | |
111 | c = s->end; |
|
111 | c = s->end; | |
112 | l = cut - offset - s->start; |
|
112 | l = cut - offset - s->start; | |
113 | if (s->len < l) |
|
113 | if (s->len < l) | |
114 | l = s->len; |
|
114 | l = s->len; | |
115 |
|
115 | |||
116 | offset += s->start + l - c; |
|
116 | offset += s->start + l - c; | |
117 |
|
117 | |||
118 | d->start = s->start; |
|
118 | d->start = s->start; | |
119 | d->end = c; |
|
119 | d->end = c; | |
120 | d->len = l; |
|
120 | d->len = l; | |
121 | d->data = s->data; |
|
121 | d->data = s->data; | |
122 | d++; |
|
122 | d++; | |
123 | s->start = c; |
|
123 | s->start = c; | |
124 | s->len = s->len - l; |
|
124 | s->len = s->len - l; | |
125 | s->data = s->data + l; |
|
125 | s->data = s->data + l; | |
126 |
|
126 | |||
127 | break; |
|
127 | break; | |
128 | } |
|
128 | } | |
129 | } |
|
129 | } | |
130 |
|
130 | |||
131 | dest->tail = d; |
|
131 | dest->tail = d; | |
132 | src->head = s; |
|
132 | src->head = s; | |
133 | return offset; |
|
133 | return offset; | |
134 | } |
|
134 | } | |
135 |
|
135 | |||
136 | /* like gather, but with no output list */ |
|
136 | /* like gather, but with no output list */ | |
137 | static int discard(struct flist *src, int cut, int offset) |
|
137 | static int discard(struct flist *src, int cut, int offset) | |
138 | { |
|
138 | { | |
139 | struct frag *s = src->head; |
|
139 | struct frag *s = src->head; | |
140 | int postend, c, l; |
|
140 | int postend, c, l; | |
141 |
|
141 | |||
142 | while (s != src->tail) { |
|
142 | while (s != src->tail) { | |
143 | if (s->start + offset >= cut) |
|
143 | if (s->start + offset >= cut) | |
144 | break; |
|
144 | break; | |
145 |
|
145 | |||
146 | postend = offset + s->start + s->len; |
|
146 | postend = offset + s->start + s->len; | |
147 | if (postend <= cut) { |
|
147 | if (postend <= cut) { | |
148 | offset += s->start + s->len - s->end; |
|
148 | offset += s->start + s->len - s->end; | |
149 | s++; |
|
149 | s++; | |
150 | } |
|
150 | } | |
151 | else { |
|
151 | else { | |
152 | c = cut - offset; |
|
152 | c = cut - offset; | |
153 | if (s->end < c) |
|
153 | if (s->end < c) | |
154 | c = s->end; |
|
154 | c = s->end; | |
155 | l = cut - offset - s->start; |
|
155 | l = cut - offset - s->start; | |
156 | if (s->len < l) |
|
156 | if (s->len < l) | |
157 | l = s->len; |
|
157 | l = s->len; | |
158 |
|
158 | |||
159 | offset += s->start + l - c; |
|
159 | offset += s->start + l - c; | |
160 | s->start = c; |
|
160 | s->start = c; | |
161 | s->len = s->len - l; |
|
161 | s->len = s->len - l; | |
162 | s->data = s->data + l; |
|
162 | s->data = s->data + l; | |
163 |
|
163 | |||
164 | break; |
|
164 | break; | |
165 | } |
|
165 | } | |
166 | } |
|
166 | } | |
167 |
|
167 | |||
168 | src->head = s; |
|
168 | src->head = s; | |
169 | return offset; |
|
169 | return offset; | |
170 | } |
|
170 | } | |
171 |
|
171 | |||
172 | /* combine hunk lists a and b, while adjusting b for offset changes in a/ |
|
172 | /* combine hunk lists a and b, while adjusting b for offset changes in a/ | |
173 | this deletes a and b and returns the resultant list. */ |
|
173 | this deletes a and b and returns the resultant list. */ | |
174 | static struct flist *combine(struct flist *a, struct flist *b) |
|
174 | static struct flist *combine(struct flist *a, struct flist *b) | |
175 | { |
|
175 | { | |
176 | struct flist *c = NULL; |
|
176 | struct flist *c = NULL; | |
177 | struct frag *bh, *ct; |
|
177 | struct frag *bh, *ct; | |
178 | int offset = 0, post; |
|
178 | int offset = 0, post; | |
179 |
|
179 | |||
180 | if (a && b) |
|
180 | if (a && b) | |
181 | c = lalloc((lsize(a) + lsize(b)) * 2); |
|
181 | c = lalloc((lsize(a) + lsize(b)) * 2); | |
182 |
|
182 | |||
183 | if (c) { |
|
183 | if (c) { | |
184 |
|
184 | |||
185 | for (bh = b->head; bh != b->tail; bh++) { |
|
185 | for (bh = b->head; bh != b->tail; bh++) { | |
186 | /* save old hunks */ |
|
186 | /* save old hunks */ | |
187 | offset = gather(c, a, bh->start, offset); |
|
187 | offset = gather(c, a, bh->start, offset); | |
188 |
|
188 | |||
189 | /* discard replaced hunks */ |
|
189 | /* discard replaced hunks */ | |
190 | post = discard(a, bh->end, offset); |
|
190 | post = discard(a, bh->end, offset); | |
191 |
|
191 | |||
192 | /* insert new hunk */ |
|
192 | /* insert new hunk */ | |
193 | ct = c->tail; |
|
193 | ct = c->tail; | |
194 | ct->start = bh->start - offset; |
|
194 | ct->start = bh->start - offset; | |
195 | ct->end = bh->end - post; |
|
195 | ct->end = bh->end - post; | |
196 | ct->len = bh->len; |
|
196 | ct->len = bh->len; | |
197 | ct->data = bh->data; |
|
197 | ct->data = bh->data; | |
198 | c->tail++; |
|
198 | c->tail++; | |
199 | offset = post; |
|
199 | offset = post; | |
200 | } |
|
200 | } | |
201 |
|
201 | |||
202 | /* hold on to tail from a */ |
|
202 | /* hold on to tail from a */ | |
203 | memcpy(c->tail, a->head, sizeof(struct frag) * lsize(a)); |
|
203 | memcpy(c->tail, a->head, sizeof(struct frag) * lsize(a)); | |
204 | c->tail += lsize(a); |
|
204 | c->tail += lsize(a); | |
205 | } |
|
205 | } | |
206 |
|
206 | |||
207 | lfree(a); |
|
207 | lfree(a); | |
208 | lfree(b); |
|
208 | lfree(b); | |
209 | return c; |
|
209 | return c; | |
210 | } |
|
210 | } | |
211 |
|
211 | |||
212 | /* decode a binary patch into a hunk list */ |
|
212 | /* decode a binary patch into a hunk list */ | |
213 | static struct flist *decode(char *bin, int len) |
|
213 | static struct flist *decode(char *bin, int len) | |
214 | { |
|
214 | { | |
215 | struct flist *l; |
|
215 | struct flist *l; | |
216 | struct frag *lt; |
|
216 | struct frag *lt; | |
217 | char *end = bin + len; |
|
217 | char *end = bin + len; | |
218 | char decode[12]; /* for dealing with alignment issues */ |
|
218 | char decode[12]; /* for dealing with alignment issues */ | |
219 |
|
219 | |||
220 | /* assume worst case size, we won't have many of these lists */ |
|
220 | /* assume worst case size, we won't have many of these lists */ | |
221 | l = lalloc(len / 12); |
|
221 | l = lalloc(len / 12); | |
222 | if (!l) |
|
222 | if (!l) | |
223 | return NULL; |
|
223 | return NULL; | |
224 |
|
224 | |||
225 | lt = l->tail; |
|
225 | lt = l->tail; | |
226 |
|
226 | |||
227 | while (bin < end) { |
|
227 | while (bin < end) { | |
228 | memcpy(decode, bin, 12); |
|
228 | memcpy(decode, bin, 12); | |
229 | lt->start = ntohl(*(uint32_t *)decode); |
|
229 | lt->start = ntohl(*(uint32_t *)decode); | |
230 | lt->end = ntohl(*(uint32_t *)(decode + 4)); |
|
230 | lt->end = ntohl(*(uint32_t *)(decode + 4)); | |
231 | lt->len = ntohl(*(uint32_t *)(decode + 8)); |
|
231 | lt->len = ntohl(*(uint32_t *)(decode + 8)); | |
232 | lt->data = bin + 12; |
|
232 | lt->data = bin + 12; | |
233 | bin += 12 + lt->len; |
|
233 | bin += 12 + lt->len; | |
234 | lt++; |
|
234 | lt++; | |
235 | } |
|
235 | } | |
236 |
|
236 | |||
237 | if (bin != end) { |
|
237 | if (bin != end) { | |
238 | if (!PyErr_Occurred()) |
|
238 | if (!PyErr_Occurred()) | |
239 | PyErr_SetString(mpatch_Error, "patch cannot be decoded"); |
|
239 | PyErr_SetString(mpatch_Error, "patch cannot be decoded"); | |
240 | lfree(l); |
|
240 | lfree(l); | |
241 | return NULL; |
|
241 | return NULL; | |
242 | } |
|
242 | } | |
243 |
|
243 | |||
244 | l->tail = lt; |
|
244 | l->tail = lt; | |
245 | return l; |
|
245 | return l; | |
246 | } |
|
246 | } | |
247 |
|
247 | |||
248 | /* calculate the size of resultant text */ |
|
248 | /* calculate the size of resultant text */ | |
249 | static int calcsize(int len, struct flist *l) |
|
249 | static int calcsize(int len, struct flist *l) | |
250 | { |
|
250 | { | |
251 | int outlen = 0, last = 0; |
|
251 | int outlen = 0, last = 0; | |
252 | struct frag *f = l->head; |
|
252 | struct frag *f = l->head; | |
253 |
|
253 | |||
254 | while (f != l->tail) { |
|
254 | while (f != l->tail) { | |
255 | if (f->start < last || f->end > len) { |
|
255 | if (f->start < last || f->end > len) { | |
256 | if (!PyErr_Occurred()) |
|
256 | if (!PyErr_Occurred()) | |
257 | PyErr_SetString(mpatch_Error, |
|
257 | PyErr_SetString(mpatch_Error, | |
258 | "invalid patch"); |
|
258 | "invalid patch"); | |
259 | return -1; |
|
259 | return -1; | |
260 | } |
|
260 | } | |
261 | outlen += f->start - last; |
|
261 | outlen += f->start - last; | |
262 | last = f->end; |
|
262 | last = f->end; | |
263 | outlen += f->len; |
|
263 | outlen += f->len; | |
264 | f++; |
|
264 | f++; | |
265 | } |
|
265 | } | |
266 |
|
266 | |||
267 | outlen += len - last; |
|
267 | outlen += len - last; | |
268 | return outlen; |
|
268 | return outlen; | |
269 | } |
|
269 | } | |
270 |
|
270 | |||
271 | static int apply(char *buf, char *orig, int len, struct flist *l) |
|
271 | static int apply(char *buf, char *orig, int len, struct flist *l) | |
272 | { |
|
272 | { | |
273 | struct frag *f = l->head; |
|
273 | struct frag *f = l->head; | |
274 | int last = 0; |
|
274 | int last = 0; | |
275 | char *p = buf; |
|
275 | char *p = buf; | |
276 |
|
276 | |||
277 | while (f != l->tail) { |
|
277 | while (f != l->tail) { | |
278 | if (f->start < last || f->end > len) { |
|
278 | if (f->start < last || f->end > len) { | |
279 | if (!PyErr_Occurred()) |
|
279 | if (!PyErr_Occurred()) | |
280 | PyErr_SetString(mpatch_Error, |
|
280 | PyErr_SetString(mpatch_Error, | |
281 | "invalid patch"); |
|
281 | "invalid patch"); | |
282 | return 0; |
|
282 | return 0; | |
283 | } |
|
283 | } | |
284 | memcpy(p, orig + last, f->start - last); |
|
284 | memcpy(p, orig + last, f->start - last); | |
285 | p += f->start - last; |
|
285 | p += f->start - last; | |
286 | memcpy(p, f->data, f->len); |
|
286 | memcpy(p, f->data, f->len); | |
287 | last = f->end; |
|
287 | last = f->end; | |
288 | p += f->len; |
|
288 | p += f->len; | |
289 | f++; |
|
289 | f++; | |
290 | } |
|
290 | } | |
291 | memcpy(p, orig + last, len - last); |
|
291 | memcpy(p, orig + last, len - last); | |
292 | return 1; |
|
292 | return 1; | |
293 | } |
|
293 | } | |
294 |
|
294 | |||
295 | /* recursively generate a patch of all bins between start and end */ |
|
295 | /* recursively generate a patch of all bins between start and end */ | |
296 | static struct flist *fold(PyObject *bins, int start, int end) |
|
296 | static struct flist *fold(PyObject *bins, int start, int end) | |
297 | { |
|
297 | { | |
298 | int len; |
|
298 | int len; | |
299 |
|
299 | |||
300 | if (start + 1 == end) { |
|
300 | if (start + 1 == end) { | |
301 | /* trivial case, output a decoded list */ |
|
301 | /* trivial case, output a decoded list */ | |
302 | PyObject *tmp = PyList_GetItem(bins, start); |
|
302 | PyObject *tmp = PyList_GetItem(bins, start); | |
303 | if (!tmp) |
|
303 | if (!tmp) | |
304 | return NULL; |
|
304 | return NULL; | |
305 | return decode(PyString_AsString(tmp), PyString_Size(tmp)); |
|
305 | return decode(PyString_AsString(tmp), PyString_Size(tmp)); | |
306 | } |
|
306 | } | |
307 |
|
307 | |||
308 | /* divide and conquer, memory management is elsewhere */ |
|
308 | /* divide and conquer, memory management is elsewhere */ | |
309 | len = (end - start) / 2; |
|
309 | len = (end - start) / 2; | |
310 | return combine(fold(bins, start, start + len), |
|
310 | return combine(fold(bins, start, start + len), | |
311 | fold(bins, start + len, end)); |
|
311 | fold(bins, start + len, end)); | |
312 | } |
|
312 | } | |
313 |
|
313 | |||
314 | static PyObject * |
|
314 | static PyObject * | |
315 | patches(PyObject *self, PyObject *args) |
|
315 | patches(PyObject *self, PyObject *args) | |
316 | { |
|
316 | { | |
317 | PyObject *text, *bins, *result; |
|
317 | PyObject *text, *bins, *result; | |
318 | struct flist *patch; |
|
318 | struct flist *patch; | |
319 | char *in, *out; |
|
319 | char *in, *out; | |
320 | int len, outlen; |
|
320 | int len, outlen; | |
321 |
|
321 | |||
322 | if (!PyArg_ParseTuple(args, "SO:mpatch", &text, &bins)) |
|
322 | if (!PyArg_ParseTuple(args, "SO:mpatch", &text, &bins)) | |
323 | return NULL; |
|
323 | return NULL; | |
324 |
|
324 | |||
325 | len = PyList_Size(bins); |
|
325 | len = PyList_Size(bins); | |
326 | if (!len) { |
|
326 | if (!len) { | |
327 | /* nothing to do */ |
|
327 | /* nothing to do */ | |
328 | Py_INCREF(text); |
|
328 | Py_INCREF(text); | |
329 | return text; |
|
329 | return text; | |
330 | } |
|
330 | } | |
331 |
|
331 | |||
332 | patch = fold(bins, 0, len); |
|
332 | patch = fold(bins, 0, len); | |
333 | if (!patch) |
|
333 | if (!patch) | |
334 | return NULL; |
|
334 | return NULL; | |
335 |
|
335 | |||
336 | outlen = calcsize(PyString_Size(text), patch); |
|
336 | outlen = calcsize(PyString_Size(text), patch); | |
337 | if (outlen < 0) { |
|
337 | if (outlen < 0) { | |
338 | result = NULL; |
|
338 | result = NULL; | |
339 | goto cleanup; |
|
339 | goto cleanup; | |
340 | } |
|
340 | } | |
341 | result = PyString_FromStringAndSize(NULL, outlen); |
|
341 | result = PyString_FromStringAndSize(NULL, outlen); | |
342 | if (!result) { |
|
342 | if (!result) { | |
343 | result = NULL; |
|
343 | result = NULL; | |
344 | goto cleanup; |
|
344 | goto cleanup; | |
345 | } |
|
345 | } | |
346 | in = PyString_AsString(text); |
|
346 | in = PyString_AsString(text); | |
347 | out = PyString_AsString(result); |
|
347 | out = PyString_AsString(result); | |
348 | if (!apply(out, in, PyString_Size(text), patch)) { |
|
348 | if (!apply(out, in, PyString_Size(text), patch)) { | |
349 | Py_DECREF(result); |
|
349 | Py_DECREF(result); | |
350 | result = NULL; |
|
350 | result = NULL; | |
351 | } |
|
351 | } | |
352 | cleanup: |
|
352 | cleanup: | |
353 | lfree(patch); |
|
353 | lfree(patch); | |
354 | return result; |
|
354 | return result; | |
355 | } |
|
355 | } | |
356 |
|
356 | |||
357 | static PyMethodDef methods[] = { |
|
357 | static PyMethodDef methods[] = { | |
358 | {"patches", patches, METH_VARARGS, "apply a series of patches\n"}, |
|
358 | {"patches", patches, METH_VARARGS, "apply a series of patches\n"}, | |
359 | {NULL, NULL} |
|
359 | {NULL, NULL} | |
360 | }; |
|
360 | }; | |
361 |
|
361 | |||
362 | PyMODINIT_FUNC |
|
362 | PyMODINIT_FUNC | |
363 | initmpatch(void) |
|
363 | initmpatch(void) | |
364 | { |
|
364 | { | |
365 | Py_InitModule3("mpatch", methods, mpatch_doc); |
|
365 | Py_InitModule3("mpatch", methods, mpatch_doc); | |
366 | mpatch_Error = PyErr_NewException("mpatch.mpatchError", NULL, NULL); |
|
366 | mpatch_Error = PyErr_NewException("mpatch.mpatchError", NULL, NULL); | |
367 | } |
|
367 | } | |
368 |
|
368 |
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