freshlybakedca.ke
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1#define USE_THE_REPOSITORY_VARIABLE
2
3#include "git-compat-util.h"
4#include "config.h"
5#include "strbuf.h"
6#include "string-list.h"
7#include "versioncmp.h"
8
9/*
10 * versioncmp(): copied from string/strverscmp.c in glibc commit
11 * ee9247c38a8def24a59eb5cfb7196a98bef8cfdc, reformatted to Git coding
12 * style. The implementation is under LGPL-2.1 and Git relicenses it
13 * to GPLv2.
14 */
15
16/*
17 * states: S_N: normal, S_I: comparing integral part, S_F: comparing
18 * fractionnal parts, S_Z: idem but with leading Zeroes only
19 */
20#define S_N 0x0
21#define S_I 0x3
22#define S_F 0x6
23#define S_Z 0x9
24
25/* result_type: CMP: return diff; LEN: compare using len_diff/diff */
26#define CMP 2
27#define LEN 3
28
29static const struct string_list *prereleases;
30static int initialized;
31
32struct suffix_match {
33 int conf_pos;
34 int start;
35 int len;
36};
37
38static void find_better_matching_suffix(const char *tagname, const char *suffix,
39 int suffix_len, int start, int conf_pos,
40 struct suffix_match *match)
41{
42 /*
43 * A better match either starts earlier or starts at the same offset
44 * but is longer.
45 */
46 int end = match->len < suffix_len ? match->start : match->start-1;
47 int i;
48 for (i = start; i <= end; i++)
49 if (starts_with(tagname + i, suffix)) {
50 match->conf_pos = conf_pos;
51 match->start = i;
52 match->len = suffix_len;
53 break;
54 }
55}
56
57/*
58 * off is the offset of the first different character in the two strings
59 * s1 and s2. If either s1 or s2 contains a prerelease suffix containing
60 * that offset or a suffix ends right before that offset, then that
61 * string will be forced to be on top.
62 *
63 * If both s1 and s2 contain a (different) suffix around that position,
64 * their order is determined by the order of those two suffixes in the
65 * configuration.
66 * If any of the strings contains more than one different suffixes around
67 * that position, then that string is sorted according to the contained
68 * suffix which starts at the earliest offset in that string.
69 * If more than one different contained suffixes start at that earliest
70 * offset, then that string is sorted according to the longest of those
71 * suffixes.
72 *
73 * Return non-zero if *diff contains the return value for versioncmp()
74 */
75static int swap_prereleases(const char *s1,
76 const char *s2,
77 int off,
78 int *diff)
79{
80 struct suffix_match match1 = { -1, off, -1 };
81 struct suffix_match match2 = { -1, off, -1 };
82
83 for (size_t i = 0; i < prereleases->nr; i++) {
84 const char *suffix = prereleases->items[i].string;
85 int start, suffix_len = strlen(suffix);
86 if (suffix_len < off)
87 start = off - suffix_len;
88 else
89 start = 0;
90 find_better_matching_suffix(s1, suffix, suffix_len, start,
91 i, &match1);
92 find_better_matching_suffix(s2, suffix, suffix_len, start,
93 i, &match2);
94 }
95 if (match1.conf_pos == -1 && match2.conf_pos == -1)
96 return 0;
97 if (match1.conf_pos == match2.conf_pos)
98 /* Found the same suffix in both, e.g. "-rc" in "v1.0-rcX"
99 * and "v1.0-rcY": the caller should decide based on "X"
100 * and "Y". */
101 return 0;
102
103 if (match1.conf_pos >= 0 && match2.conf_pos >= 0)
104 *diff = match1.conf_pos - match2.conf_pos;
105 else if (match1.conf_pos >= 0)
106 *diff = -1;
107 else /* if (match2.conf_pos >= 0) */
108 *diff = 1;
109 return 1;
110}
111
112/*
113 * Compare S1 and S2 as strings holding indices/version numbers,
114 * returning less than, equal to or greater than zero if S1 is less
115 * than, equal to or greater than S2 (for more info, see the texinfo
116 * doc).
117 */
118
119int versioncmp(const char *s1, const char *s2)
120{
121 const unsigned char *p1 = (const unsigned char *) s1;
122 const unsigned char *p2 = (const unsigned char *) s2;
123 unsigned char c1, c2;
124 int state, diff;
125
126 /*
127 * Symbol(s) 0 [1-9] others
128 * Transition (10) 0 (01) d (00) x
129 */
130 static const uint8_t next_state[] = {
131 /* state x d 0 */
132 /* S_N */ S_N, S_I, S_Z,
133 /* S_I */ S_N, S_I, S_I,
134 /* S_F */ S_N, S_F, S_F,
135 /* S_Z */ S_N, S_F, S_Z
136 };
137
138 static const int8_t result_type[] = {
139 /* state x/x x/d x/0 d/x d/d d/0 0/x 0/d 0/0 */
140
141 /* S_N */ CMP, CMP, CMP, CMP, LEN, CMP, CMP, CMP, CMP,
142 /* S_I */ CMP, -1, -1, +1, LEN, LEN, +1, LEN, LEN,
143 /* S_F */ CMP, CMP, CMP, CMP, CMP, CMP, CMP, CMP, CMP,
144 /* S_Z */ CMP, +1, +1, -1, CMP, CMP, -1, CMP, CMP
145 };
146
147 if (p1 == p2)
148 return 0;
149
150 c1 = *p1++;
151 c2 = *p2++;
152 /* Hint: '0' is a digit too. */
153 state = S_N + ((c1 == '0') + (isdigit (c1) != 0));
154
155 while ((diff = c1 - c2) == 0) {
156 if (c1 == '\0')
157 return diff;
158
159 state = next_state[state];
160 c1 = *p1++;
161 c2 = *p2++;
162 state += (c1 == '0') + (isdigit (c1) != 0);
163 }
164
165 if (!initialized) {
166 const char *const newk = "versionsort.suffix";
167 const char *const oldk = "versionsort.prereleasesuffix";
168 const struct string_list *newl;
169 const struct string_list *oldl;
170 int new = repo_config_get_string_multi(the_repository, newk, &newl);
171 int old = repo_config_get_string_multi(the_repository, oldk, &oldl);
172
173 if (!new && !old)
174 warning("ignoring %s because %s is set", oldk, newk);
175 if (!new)
176 prereleases = newl;
177 else if (!old)
178 prereleases = oldl;
179
180 initialized = 1;
181 }
182 if (prereleases && swap_prereleases(s1, s2, (const char *) p1 - s1 - 1,
183 &diff))
184 return diff;
185
186 state = result_type[state * 3 + (((c2 == '0') + (isdigit (c2) != 0)))];
187
188 switch (state) {
189 case CMP:
190 return diff;
191
192 case LEN:
193 while (isdigit (*p1++))
194 if (!isdigit (*p2++))
195 return 1;
196
197 return isdigit (*p2) ? -1 : diff;
198
199 default:
200 return state;
201 }
202}