Merge branch 'maint'
[git/mjg.git] / ws.c
blobd7b8c33f14195ba7ebe86bdbca2fea8f1b22ad37
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:1,
14 exclude_default:1;
15 } whitespace_rule_names[] = {
16 { "trailing-space", WS_TRAILING_SPACE, 0 },
17 { "space-before-tab", WS_SPACE_BEFORE_TAB, 0 },
18 { "indent-with-non-tab", WS_INDENT_WITH_NON_TAB, 0 },
19 { "cr-at-eol", WS_CR_AT_EOL, 1 },
20 { "blank-at-eol", WS_BLANK_AT_EOL, 0 },
21 { "blank-at-eof", WS_BLANK_AT_EOF, 0 },
22 { "tab-in-indent", WS_TAB_IN_INDENT, 0, 1 },
25 unsigned parse_whitespace_rule(const char *string)
27 unsigned rule = WS_DEFAULT_RULE;
29 while (string) {
30 int i;
31 size_t len;
32 const char *ep;
33 int negated = 0;
35 string = string + strspn(string, ", \t\n\r");
36 ep = strchr(string, ',');
37 if (!ep)
38 len = strlen(string);
39 else
40 len = ep - string;
42 if (*string == '-') {
43 negated = 1;
44 string++;
45 len--;
47 if (!len)
48 break;
49 for (i = 0; i < ARRAY_SIZE(whitespace_rule_names); i++) {
50 if (strncmp(whitespace_rule_names[i].rule_name,
51 string, len))
52 continue;
53 if (negated)
54 rule &= ~whitespace_rule_names[i].rule_bits;
55 else
56 rule |= whitespace_rule_names[i].rule_bits;
57 break;
59 string = ep;
62 if (rule & WS_TAB_IN_INDENT && rule & WS_INDENT_WITH_NON_TAB)
63 die("cannot enforce both tab-in-indent and indent-with-non-tab");
64 return rule;
67 static void setup_whitespace_attr_check(struct git_attr_check *check)
69 static struct git_attr *attr_whitespace;
71 if (!attr_whitespace)
72 attr_whitespace = git_attr("whitespace");
73 check[0].attr = attr_whitespace;
76 unsigned whitespace_rule(const char *pathname)
78 struct git_attr_check attr_whitespace_rule;
80 setup_whitespace_attr_check(&attr_whitespace_rule);
81 if (!git_checkattr(pathname, 1, &attr_whitespace_rule)) {
82 const char *value;
84 value = attr_whitespace_rule.value;
85 if (ATTR_TRUE(value)) {
86 /* true (whitespace) */
87 unsigned all_rule = 0;
88 int i;
89 for (i = 0; i < ARRAY_SIZE(whitespace_rule_names); i++)
90 if (!whitespace_rule_names[i].loosens_error &&
91 !whitespace_rule_names[i].exclude_default)
92 all_rule |= whitespace_rule_names[i].rule_bits;
93 return all_rule;
94 } else if (ATTR_FALSE(value)) {
95 /* false (-whitespace) */
96 return 0;
97 } else if (ATTR_UNSET(value)) {
98 /* reset to default (!whitespace) */
99 return whitespace_rule_cfg;
100 } else {
101 /* string */
102 return parse_whitespace_rule(value);
104 } else {
105 return whitespace_rule_cfg;
109 /* The returned string should be freed by the caller. */
110 char *whitespace_error_string(unsigned ws)
112 struct strbuf err = STRBUF_INIT;
113 if ((ws & WS_TRAILING_SPACE) == WS_TRAILING_SPACE)
114 strbuf_addstr(&err, "trailing whitespace");
115 else {
116 if (ws & WS_BLANK_AT_EOL)
117 strbuf_addstr(&err, "trailing whitespace");
118 if (ws & WS_BLANK_AT_EOF) {
119 if (err.len)
120 strbuf_addstr(&err, ", ");
121 strbuf_addstr(&err, "new blank line at EOF");
124 if (ws & WS_SPACE_BEFORE_TAB) {
125 if (err.len)
126 strbuf_addstr(&err, ", ");
127 strbuf_addstr(&err, "space before tab in indent");
129 if (ws & WS_INDENT_WITH_NON_TAB) {
130 if (err.len)
131 strbuf_addstr(&err, ", ");
132 strbuf_addstr(&err, "indent with spaces");
134 if (ws & WS_TAB_IN_INDENT) {
135 if (err.len)
136 strbuf_addstr(&err, ", ");
137 strbuf_addstr(&err, "tab in indent");
139 return strbuf_detach(&err, NULL);
142 /* If stream is non-NULL, emits the line after checking. */
143 static unsigned ws_check_emit_1(const char *line, int len, unsigned ws_rule,
144 FILE *stream, const char *set,
145 const char *reset, const char *ws)
147 unsigned result = 0;
148 int written = 0;
149 int trailing_whitespace = -1;
150 int trailing_newline = 0;
151 int trailing_carriage_return = 0;
152 int i;
154 /* Logic is simpler if we temporarily ignore the trailing newline. */
155 if (len > 0 && line[len - 1] == '\n') {
156 trailing_newline = 1;
157 len--;
159 if ((ws_rule & WS_CR_AT_EOL) &&
160 len > 0 && line[len - 1] == '\r') {
161 trailing_carriage_return = 1;
162 len--;
165 /* Check for trailing whitespace. */
166 if (ws_rule & WS_BLANK_AT_EOL) {
167 for (i = len - 1; i >= 0; i--) {
168 if (isspace(line[i])) {
169 trailing_whitespace = i;
170 result |= WS_BLANK_AT_EOL;
172 else
173 break;
177 /* Check indentation */
178 for (i = 0; i < len; i++) {
179 if (line[i] == ' ')
180 continue;
181 if (line[i] != '\t')
182 break;
183 if ((ws_rule & WS_SPACE_BEFORE_TAB) && written < i) {
184 result |= WS_SPACE_BEFORE_TAB;
185 if (stream) {
186 fputs(ws, stream);
187 fwrite(line + written, i - written, 1, stream);
188 fputs(reset, stream);
189 fwrite(line + i, 1, 1, stream);
191 } else if (ws_rule & WS_TAB_IN_INDENT) {
192 result |= WS_TAB_IN_INDENT;
193 if (stream) {
194 fwrite(line + written, i - written, 1, stream);
195 fputs(ws, stream);
196 fwrite(line + i, 1, 1, stream);
197 fputs(reset, stream);
199 } else if (stream) {
200 fwrite(line + written, i - written + 1, 1, stream);
202 written = i + 1;
205 /* Check for indent using non-tab. */
206 if ((ws_rule & WS_INDENT_WITH_NON_TAB) && i - written >= 8) {
207 result |= WS_INDENT_WITH_NON_TAB;
208 if (stream) {
209 fputs(ws, stream);
210 fwrite(line + written, i - written, 1, stream);
211 fputs(reset, stream);
213 written = i;
216 if (stream) {
218 * Now the rest of the line starts at "written".
219 * The non-highlighted part ends at "trailing_whitespace".
221 if (trailing_whitespace == -1)
222 trailing_whitespace = len;
224 /* Emit non-highlighted (middle) segment. */
225 if (trailing_whitespace - written > 0) {
226 fputs(set, stream);
227 fwrite(line + written,
228 trailing_whitespace - written, 1, stream);
229 fputs(reset, stream);
232 /* Highlight errors in trailing whitespace. */
233 if (trailing_whitespace != len) {
234 fputs(ws, stream);
235 fwrite(line + trailing_whitespace,
236 len - trailing_whitespace, 1, stream);
237 fputs(reset, stream);
239 if (trailing_carriage_return)
240 fputc('\r', stream);
241 if (trailing_newline)
242 fputc('\n', stream);
244 return result;
247 void ws_check_emit(const char *line, int len, unsigned ws_rule,
248 FILE *stream, const char *set,
249 const char *reset, const char *ws)
251 (void)ws_check_emit_1(line, len, ws_rule, stream, set, reset, ws);
254 unsigned ws_check(const char *line, int len, unsigned ws_rule)
256 return ws_check_emit_1(line, len, ws_rule, NULL, NULL, NULL, NULL);
259 int ws_blank_line(const char *line, int len, unsigned ws_rule)
262 * We _might_ want to treat CR differently from other
263 * whitespace characters when ws_rule has WS_CR_AT_EOL, but
264 * for now we just use this stupid definition.
266 while (len-- > 0) {
267 if (!isspace(*line))
268 return 0;
269 line++;
271 return 1;
274 /* Copy the line onto the end of the strbuf while fixing whitespaces */
275 void ws_fix_copy(struct strbuf *dst, const char *src, int len, unsigned ws_rule, int *error_count)
278 * len is number of bytes to be copied from src, starting
279 * at src. Typically src[len-1] is '\n', unless this is
280 * the incomplete last line.
282 int i;
283 int add_nl_to_tail = 0;
284 int add_cr_to_tail = 0;
285 int fixed = 0;
286 int last_tab_in_indent = -1;
287 int last_space_in_indent = -1;
288 int need_fix_leading_space = 0;
291 * Strip trailing whitespace
293 if (ws_rule & WS_BLANK_AT_EOL) {
294 if (0 < len && src[len - 1] == '\n') {
295 add_nl_to_tail = 1;
296 len--;
297 if (0 < len && src[len - 1] == '\r') {
298 add_cr_to_tail = !!(ws_rule & WS_CR_AT_EOL);
299 len--;
302 if (0 < len && isspace(src[len - 1])) {
303 while (0 < len && isspace(src[len-1]))
304 len--;
305 fixed = 1;
310 * Check leading whitespaces (indent)
312 for (i = 0; i < len; i++) {
313 char ch = src[i];
314 if (ch == '\t') {
315 last_tab_in_indent = i;
316 if ((ws_rule & WS_SPACE_BEFORE_TAB) &&
317 0 <= last_space_in_indent)
318 need_fix_leading_space = 1;
319 } else if (ch == ' ') {
320 last_space_in_indent = i;
321 if ((ws_rule & WS_INDENT_WITH_NON_TAB) &&
322 8 <= i - last_tab_in_indent)
323 need_fix_leading_space = 1;
324 } else
325 break;
328 if (need_fix_leading_space) {
329 /* Process indent ourselves */
330 int consecutive_spaces = 0;
331 int last = last_tab_in_indent + 1;
333 if (ws_rule & WS_INDENT_WITH_NON_TAB) {
334 /* have "last" point at one past the indent */
335 if (last_tab_in_indent < last_space_in_indent)
336 last = last_space_in_indent + 1;
337 else
338 last = last_tab_in_indent + 1;
342 * between src[0..last-1], strip the funny spaces,
343 * updating them to tab as needed.
345 for (i = 0; i < last; i++) {
346 char ch = src[i];
347 if (ch != ' ') {
348 consecutive_spaces = 0;
349 strbuf_addch(dst, ch);
350 } else {
351 consecutive_spaces++;
352 if (consecutive_spaces == 8) {
353 strbuf_addch(dst, '\t');
354 consecutive_spaces = 0;
358 while (0 < consecutive_spaces--)
359 strbuf_addch(dst, ' ');
360 len -= last;
361 src += last;
362 fixed = 1;
363 } else if ((ws_rule & WS_TAB_IN_INDENT) && last_tab_in_indent >= 0) {
364 /* Expand tabs into spaces */
365 int last = last_tab_in_indent + 1;
366 for (i = 0; i < last; i++) {
367 if (src[i] == '\t')
368 do {
369 strbuf_addch(dst, ' ');
370 } while (dst->len % 8);
371 else
372 strbuf_addch(dst, src[i]);
374 len -= last;
375 src += last;
376 fixed = 1;
379 strbuf_add(dst, src, len);
380 if (add_cr_to_tail)
381 strbuf_addch(dst, '\r');
382 if (add_nl_to_tail)
383 strbuf_addch(dst, '\n');
384 if (fixed && error_count)
385 (*error_count)++;