f4201e160de2ccb9f2d9adef695c73a124e676d5
[git/git.git] / strbuf.c
1 #include "cache.h"
2
3 /*
4 * Used as the default ->buf value, so that people can always assume
5 * buf is non NULL and ->buf is NUL terminated even for a freshly
6 * initialized strbuf.
7 */
8 char strbuf_slopbuf[1];
9
10 void strbuf_init(struct strbuf *sb, size_t hint)
11 {
12 sb->alloc = sb->len = 0;
13 sb->buf = strbuf_slopbuf;
14 if (hint)
15 strbuf_grow(sb, hint);
16 }
17
18 void strbuf_release(struct strbuf *sb)
19 {
20 if (sb->alloc) {
21 free(sb->buf);
22 strbuf_init(sb, 0);
23 }
24 }
25
26 char *strbuf_detach(struct strbuf *sb, size_t *sz)
27 {
28 char *res = sb->alloc ? sb->buf : NULL;
29 if (sz)
30 *sz = sb->len;
31 strbuf_init(sb, 0);
32 return res;
33 }
34
35 void strbuf_attach(struct strbuf *sb, void *buf, size_t len, size_t alloc)
36 {
37 strbuf_release(sb);
38 sb->buf = buf;
39 sb->len = len;
40 sb->alloc = alloc;
41 strbuf_grow(sb, 0);
42 sb->buf[sb->len] = '\0';
43 }
44
45 void strbuf_grow(struct strbuf *sb, size_t extra)
46 {
47 if (sb->len + extra + 1 <= sb->len)
48 die("you want to use way too much memory");
49 if (!sb->alloc)
50 sb->buf = NULL;
51 ALLOC_GROW(sb->buf, sb->len + extra + 1, sb->alloc);
52 }
53
54 void strbuf_rtrim(struct strbuf *sb)
55 {
56 while (sb->len > 0 && isspace((unsigned char)sb->buf[sb->len - 1]))
57 sb->len--;
58 sb->buf[sb->len] = '\0';
59 }
60
61 int strbuf_cmp(struct strbuf *a, struct strbuf *b)
62 {
63 int cmp;
64 if (a->len < b->len) {
65 cmp = memcmp(a->buf, b->buf, a->len);
66 return cmp ? cmp : -1;
67 } else {
68 cmp = memcmp(a->buf, b->buf, b->len);
69 return cmp ? cmp : a->len != b->len;
70 }
71 }
72
73 void strbuf_splice(struct strbuf *sb, size_t pos, size_t len,
74 const void *data, size_t dlen)
75 {
76 if (pos + len < pos)
77 die("you want to use way too much memory");
78 if (pos > sb->len)
79 die("`pos' is too far after the end of the buffer");
80 if (pos + len > sb->len)
81 die("`pos + len' is too far after the end of the buffer");
82
83 if (dlen >= len)
84 strbuf_grow(sb, dlen - len);
85 memmove(sb->buf + pos + dlen,
86 sb->buf + pos + len,
87 sb->len - pos - len);
88 memcpy(sb->buf + pos, data, dlen);
89 strbuf_setlen(sb, sb->len + dlen - len);
90 }
91
92 void strbuf_insert(struct strbuf *sb, size_t pos, const void *data, size_t len)
93 {
94 strbuf_splice(sb, pos, 0, data, len);
95 }
96
97 void strbuf_remove(struct strbuf *sb, size_t pos, size_t len)
98 {
99 strbuf_splice(sb, pos, len, NULL, 0);
100 }
101
102 void strbuf_add(struct strbuf *sb, const void *data, size_t len)
103 {
104 strbuf_grow(sb, len);
105 memcpy(sb->buf + sb->len, data, len);
106 strbuf_setlen(sb, sb->len + len);
107 }
108
109 void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
110 {
111 int len;
112 va_list ap;
113
114 va_start(ap, fmt);
115 len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
116 va_end(ap);
117 if (len < 0) {
118 len = 0;
119 }
120 if (len > strbuf_avail(sb)) {
121 strbuf_grow(sb, len);
122 va_start(ap, fmt);
123 len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
124 va_end(ap);
125 if (len > strbuf_avail(sb)) {
126 die("this should not happen, your snprintf is broken");
127 }
128 }
129 strbuf_setlen(sb, sb->len + len);
130 }
131
132 size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *f)
133 {
134 size_t res;
135
136 strbuf_grow(sb, size);
137 res = fread(sb->buf + sb->len, 1, size, f);
138 if (res > 0) {
139 strbuf_setlen(sb, sb->len + res);
140 }
141 return res;
142 }
143
144 ssize_t strbuf_read(struct strbuf *sb, int fd, size_t hint)
145 {
146 size_t oldlen = sb->len;
147
148 strbuf_grow(sb, hint ? hint : 8192);
149 for (;;) {
150 ssize_t cnt;
151
152 cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
153 if (cnt < 0) {
154 strbuf_setlen(sb, oldlen);
155 return -1;
156 }
157 if (!cnt)
158 break;
159 sb->len += cnt;
160 strbuf_grow(sb, 8192);
161 }
162
163 sb->buf[sb->len] = '\0';
164 return sb->len - oldlen;
165 }
166
167 int strbuf_getline(struct strbuf *sb, FILE *fp, int term)
168 {
169 int ch;
170
171 strbuf_grow(sb, 0);
172 if (feof(fp))
173 return EOF;
174
175 strbuf_reset(sb);
176 while ((ch = fgetc(fp)) != EOF) {
177 if (ch == term)
178 break;
179 strbuf_grow(sb, 1);
180 sb->buf[sb->len++] = ch;
181 }
182 if (ch == EOF && sb->len == 0)
183 return EOF;
184
185 sb->buf[sb->len] = '\0';
186 return 0;
187 }
188
189 int strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
190 {
191 int fd, len;
192
193 fd = open(path, O_RDONLY);
194 if (fd < 0)
195 return -1;
196 len = strbuf_read(sb, fd, hint);
197 close(fd);
198 if (len < 0)
199 return -1;
200
201 return len;
202 }