revert: use strbuf to refactor the code that writes the merge message
[git/dscho.git] / ws.c
blobc0893386e6c8aa3af002e847d228dfc5ef64a9cf
1 /*
2 * Whitespace rules
4 * Copyright (c) 2007 Junio C Hamano
5 */
7 #include "cache.h"
8 #include "attr.h"
10 static struct whitespace_rule {
11 const char *rule_name;
12 unsigned rule_bits;
13 unsigned loosens_error;
14 } whitespace_rule_names[] = {
15 { "trailing-space", WS_TRAILING_SPACE, 0 },
16 { "space-before-tab", WS_SPACE_BEFORE_TAB, 0 },
17 { "indent-with-non-tab", WS_INDENT_WITH_NON_TAB, 0 },
18 { "cr-at-eol", WS_CR_AT_EOL, 1 },
19 { "blank-at-eol", WS_BLANK_AT_EOL, 0 },
20 { "blank-at-eof", WS_BLANK_AT_EOF, 0 },
23 unsigned parse_whitespace_rule(const char *string)
25 unsigned rule = WS_DEFAULT_RULE;
27 while (string) {
28 int i;
29 size_t len;
30 const char *ep;
31 int negated = 0;
33 string = string + strspn(string, ", \t\n\r");
34 ep = strchr(string, ',');
35 if (!ep)
36 len = strlen(string);
37 else
38 len = ep - string;
40 if (*string == '-') {
41 negated = 1;
42 string++;
43 len--;
45 if (!len)
46 break;
47 for (i = 0; i < ARRAY_SIZE(whitespace_rule_names); i++) {
48 if (strncmp(whitespace_rule_names[i].rule_name,
49 string, len))
50 continue;
51 if (negated)
52 rule &= ~whitespace_rule_names[i].rule_bits;
53 else
54 rule |= whitespace_rule_names[i].rule_bits;
55 break;
57 string = ep;
59 return rule;
62 static void setup_whitespace_attr_check(struct git_attr_check *check)
64 static struct git_attr *attr_whitespace;
66 if (!attr_whitespace)
67 attr_whitespace = git_attr("whitespace");
68 check[0].attr = attr_whitespace;
71 unsigned whitespace_rule(const char *pathname)
73 struct git_attr_check attr_whitespace_rule;
75 setup_whitespace_attr_check(&attr_whitespace_rule);
76 if (!git_checkattr(pathname, 1, &attr_whitespace_rule)) {
77 const char *value;
79 value = attr_whitespace_rule.value;
80 if (ATTR_TRUE(value)) {
81 /* true (whitespace) */
82 unsigned all_rule = 0;
83 int i;
84 for (i = 0; i < ARRAY_SIZE(whitespace_rule_names); i++)
85 if (!whitespace_rule_names[i].loosens_error)
86 all_rule |= whitespace_rule_names[i].rule_bits;
87 return all_rule;
88 } else if (ATTR_FALSE(value)) {
89 /* false (-whitespace) */
90 return 0;
91 } else if (ATTR_UNSET(value)) {
92 /* reset to default (!whitespace) */
93 return whitespace_rule_cfg;
94 } else {
95 /* string */
96 return parse_whitespace_rule(value);
98 } else {
99 return whitespace_rule_cfg;
103 /* The returned string should be freed by the caller. */
104 char *whitespace_error_string(unsigned ws)
106 struct strbuf err = STRBUF_INIT;
107 if ((ws & WS_TRAILING_SPACE) == WS_TRAILING_SPACE)
108 strbuf_addstr(&err, "trailing whitespace");
109 else {
110 if (ws & WS_BLANK_AT_EOL)
111 strbuf_addstr(&err, "trailing whitespace");
112 if (ws & WS_BLANK_AT_EOF) {
113 if (err.len)
114 strbuf_addstr(&err, ", ");
115 strbuf_addstr(&err, "new blank line at EOF");
118 if (ws & WS_SPACE_BEFORE_TAB) {
119 if (err.len)
120 strbuf_addstr(&err, ", ");
121 strbuf_addstr(&err, "space before tab in indent");
123 if (ws & WS_INDENT_WITH_NON_TAB) {
124 if (err.len)
125 strbuf_addstr(&err, ", ");
126 strbuf_addstr(&err, "indent with spaces");
128 return strbuf_detach(&err, NULL);
131 /* If stream is non-NULL, emits the line after checking. */
132 static unsigned ws_check_emit_1(const char *line, int len, unsigned ws_rule,
133 FILE *stream, const char *set,
134 const char *reset, const char *ws)
136 unsigned result = 0;
137 int written = 0;
138 int trailing_whitespace = -1;
139 int trailing_newline = 0;
140 int trailing_carriage_return = 0;
141 int i;
143 /* Logic is simpler if we temporarily ignore the trailing newline. */
144 if (len > 0 && line[len - 1] == '\n') {
145 trailing_newline = 1;
146 len--;
148 if ((ws_rule & WS_CR_AT_EOL) &&
149 len > 0 && line[len - 1] == '\r') {
150 trailing_carriage_return = 1;
151 len--;
154 /* Check for trailing whitespace. */
155 if (ws_rule & WS_BLANK_AT_EOL) {
156 for (i = len - 1; i >= 0; i--) {
157 if (isspace(line[i])) {
158 trailing_whitespace = i;
159 result |= WS_BLANK_AT_EOL;
161 else
162 break;
166 /* Check for space before tab in initial indent. */
167 for (i = 0; i < len; i++) {
168 if (line[i] == ' ')
169 continue;
170 if (line[i] != '\t')
171 break;
172 if ((ws_rule & WS_SPACE_BEFORE_TAB) && written < i) {
173 result |= WS_SPACE_BEFORE_TAB;
174 if (stream) {
175 fputs(ws, stream);
176 fwrite(line + written, i - written, 1, stream);
177 fputs(reset, stream);
179 } else if (stream)
180 fwrite(line + written, i - written, 1, stream);
181 if (stream)
182 fwrite(line + i, 1, 1, stream);
183 written = i + 1;
186 /* Check for indent using non-tab. */
187 if ((ws_rule & WS_INDENT_WITH_NON_TAB) && i - written >= 8) {
188 result |= WS_INDENT_WITH_NON_TAB;
189 if (stream) {
190 fputs(ws, stream);
191 fwrite(line + written, i - written, 1, stream);
192 fputs(reset, stream);
194 written = i;
197 if (stream) {
199 * Now the rest of the line starts at "written".
200 * The non-highlighted part ends at "trailing_whitespace".
202 if (trailing_whitespace == -1)
203 trailing_whitespace = len;
205 /* Emit non-highlighted (middle) segment. */
206 if (trailing_whitespace - written > 0) {
207 fputs(set, stream);
208 fwrite(line + written,
209 trailing_whitespace - written, 1, stream);
210 fputs(reset, stream);
213 /* Highlight errors in trailing whitespace. */
214 if (trailing_whitespace != len) {
215 fputs(ws, stream);
216 fwrite(line + trailing_whitespace,
217 len - trailing_whitespace, 1, stream);
218 fputs(reset, stream);
220 if (trailing_carriage_return)
221 fputc('\r', stream);
222 if (trailing_newline)
223 fputc('\n', stream);
225 return result;
228 void ws_check_emit(const char *line, int len, unsigned ws_rule,
229 FILE *stream, const char *set,
230 const char *reset, const char *ws)
232 (void)ws_check_emit_1(line, len, ws_rule, stream, set, reset, ws);
235 unsigned ws_check(const char *line, int len, unsigned ws_rule)
237 return ws_check_emit_1(line, len, ws_rule, NULL, NULL, NULL, NULL);
240 int ws_blank_line(const char *line, int len, unsigned ws_rule)
243 * We _might_ want to treat CR differently from other
244 * whitespace characters when ws_rule has WS_CR_AT_EOL, but
245 * for now we just use this stupid definition.
247 while (len-- > 0) {
248 if (!isspace(*line))
249 return 0;
250 line++;
252 return 1;
255 /* Copy the line to the buffer while fixing whitespaces */
256 int ws_fix_copy(char *dst, const char *src, int len, unsigned ws_rule, int *error_count)
259 * len is number of bytes to be copied from src, starting
260 * at src. Typically src[len-1] is '\n', unless this is
261 * the incomplete last line.
263 int i;
264 int add_nl_to_tail = 0;
265 int add_cr_to_tail = 0;
266 int fixed = 0;
267 int last_tab_in_indent = -1;
268 int last_space_in_indent = -1;
269 int need_fix_leading_space = 0;
270 char *buf;
273 * Strip trailing whitespace
275 if (ws_rule & WS_BLANK_AT_EOL) {
276 if (0 < len && src[len - 1] == '\n') {
277 add_nl_to_tail = 1;
278 len--;
279 if (0 < len && src[len - 1] == '\r') {
280 add_cr_to_tail = !!(ws_rule & WS_CR_AT_EOL);
281 len--;
284 if (0 < len && isspace(src[len - 1])) {
285 while (0 < len && isspace(src[len-1]))
286 len--;
287 fixed = 1;
292 * Check leading whitespaces (indent)
294 for (i = 0; i < len; i++) {
295 char ch = src[i];
296 if (ch == '\t') {
297 last_tab_in_indent = i;
298 if ((ws_rule & WS_SPACE_BEFORE_TAB) &&
299 0 <= last_space_in_indent)
300 need_fix_leading_space = 1;
301 } else if (ch == ' ') {
302 last_space_in_indent = i;
303 if ((ws_rule & WS_INDENT_WITH_NON_TAB) &&
304 8 <= i - last_tab_in_indent)
305 need_fix_leading_space = 1;
306 } else
307 break;
310 buf = dst;
311 if (need_fix_leading_space) {
312 /* Process indent ourselves */
313 int consecutive_spaces = 0;
314 int last = last_tab_in_indent + 1;
316 if (ws_rule & WS_INDENT_WITH_NON_TAB) {
317 /* have "last" point at one past the indent */
318 if (last_tab_in_indent < last_space_in_indent)
319 last = last_space_in_indent + 1;
320 else
321 last = last_tab_in_indent + 1;
325 * between src[0..last-1], strip the funny spaces,
326 * updating them to tab as needed.
328 for (i = 0; i < last; i++) {
329 char ch = src[i];
330 if (ch != ' ') {
331 consecutive_spaces = 0;
332 *dst++ = ch;
333 } else {
334 consecutive_spaces++;
335 if (consecutive_spaces == 8) {
336 *dst++ = '\t';
337 consecutive_spaces = 0;
341 while (0 < consecutive_spaces--)
342 *dst++ = ' ';
343 len -= last;
344 src += last;
345 fixed = 1;
348 memcpy(dst, src, len);
349 if (add_cr_to_tail)
350 dst[len++] = '\r';
351 if (add_nl_to_tail)
352 dst[len++] = '\n';
353 if (fixed && error_count)
354 (*error_count)++;
355 return dst + len - buf;