Merge branch 'rb/hpe'
[git.git] / ws.c
blob6e69877f25791632d98bf7b109a2eaebd04c96af
1 /*
2 * Whitespace rules
4 * Copyright (c) 2007 Junio C Hamano
5 */
6 #include "cache.h"
7 #include "attr.h"
9 static struct whitespace_rule {
10 const char *rule_name;
11 unsigned rule_bits;
12 unsigned loosens_error:1,
13 exclude_default:1;
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 },
21 { "tab-in-indent", WS_TAB_IN_INDENT, 0, 1 },
24 unsigned parse_whitespace_rule(const char *string)
26 unsigned rule = WS_DEFAULT_RULE;
28 while (string) {
29 int i;
30 size_t len;
31 const char *ep;
32 int negated = 0;
34 string = string + strspn(string, ", \t\n\r");
35 ep = strchrnul(string, ',');
36 len = ep - string;
38 if (*string == '-') {
39 negated = 1;
40 string++;
41 len--;
43 if (!len)
44 break;
45 for (i = 0; i < ARRAY_SIZE(whitespace_rule_names); i++) {
46 if (strncmp(whitespace_rule_names[i].rule_name,
47 string, len))
48 continue;
49 if (negated)
50 rule &= ~whitespace_rule_names[i].rule_bits;
51 else
52 rule |= whitespace_rule_names[i].rule_bits;
53 break;
55 if (strncmp(string, "tabwidth=", 9) == 0) {
56 unsigned tabwidth = atoi(string + 9);
57 if (0 < tabwidth && tabwidth < 0100) {
58 rule &= ~WS_TAB_WIDTH_MASK;
59 rule |= tabwidth;
61 else
62 warning("tabwidth %.*s out of range",
63 (int)(len - 9), string + 9);
65 string = ep;
68 if (rule & WS_TAB_IN_INDENT && rule & WS_INDENT_WITH_NON_TAB)
69 die("cannot enforce both tab-in-indent and indent-with-non-tab");
70 return rule;
73 unsigned whitespace_rule(struct index_state *istate, const char *pathname)
75 static struct attr_check *attr_whitespace_rule;
76 const char *value;
78 if (!attr_whitespace_rule)
79 attr_whitespace_rule = attr_check_initl("whitespace", NULL);
81 git_check_attr(istate, pathname, attr_whitespace_rule);
82 value = attr_whitespace_rule->items[0].value;
83 if (ATTR_TRUE(value)) {
84 /* true (whitespace) */
85 unsigned all_rule = ws_tab_width(whitespace_rule_cfg);
86 int i;
87 for (i = 0; i < ARRAY_SIZE(whitespace_rule_names); i++)
88 if (!whitespace_rule_names[i].loosens_error &&
89 !whitespace_rule_names[i].exclude_default)
90 all_rule |= whitespace_rule_names[i].rule_bits;
91 return all_rule;
92 } else if (ATTR_FALSE(value)) {
93 /* false (-whitespace) */
94 return ws_tab_width(whitespace_rule_cfg);
95 } else if (ATTR_UNSET(value)) {
96 /* reset to default (!whitespace) */
97 return whitespace_rule_cfg;
98 } else {
99 /* string */
100 return parse_whitespace_rule(value);
104 /* The returned string should be freed by the caller. */
105 char *whitespace_error_string(unsigned ws)
107 struct strbuf err = STRBUF_INIT;
108 if ((ws & WS_TRAILING_SPACE) == WS_TRAILING_SPACE)
109 strbuf_addstr(&err, "trailing whitespace");
110 else {
111 if (ws & WS_BLANK_AT_EOL)
112 strbuf_addstr(&err, "trailing whitespace");
113 if (ws & WS_BLANK_AT_EOF) {
114 if (err.len)
115 strbuf_addstr(&err, ", ");
116 strbuf_addstr(&err, "new blank line at EOF");
119 if (ws & WS_SPACE_BEFORE_TAB) {
120 if (err.len)
121 strbuf_addstr(&err, ", ");
122 strbuf_addstr(&err, "space before tab in indent");
124 if (ws & WS_INDENT_WITH_NON_TAB) {
125 if (err.len)
126 strbuf_addstr(&err, ", ");
127 strbuf_addstr(&err, "indent with spaces");
129 if (ws & WS_TAB_IN_INDENT) {
130 if (err.len)
131 strbuf_addstr(&err, ", ");
132 strbuf_addstr(&err, "tab in indent");
134 return strbuf_detach(&err, NULL);
137 /* If stream is non-NULL, emits the line after checking. */
138 static unsigned ws_check_emit_1(const char *line, int len, unsigned ws_rule,
139 FILE *stream, const char *set,
140 const char *reset, const char *ws)
142 unsigned result = 0;
143 int written = 0;
144 int trailing_whitespace = -1;
145 int trailing_newline = 0;
146 int trailing_carriage_return = 0;
147 int i;
149 /* Logic is simpler if we temporarily ignore the trailing newline. */
150 if (len > 0 && line[len - 1] == '\n') {
151 trailing_newline = 1;
152 len--;
154 if ((ws_rule & WS_CR_AT_EOL) &&
155 len > 0 && line[len - 1] == '\r') {
156 trailing_carriage_return = 1;
157 len--;
160 /* Check for trailing whitespace. */
161 if (ws_rule & WS_BLANK_AT_EOL) {
162 for (i = len - 1; i >= 0; i--) {
163 if (isspace(line[i])) {
164 trailing_whitespace = i;
165 result |= WS_BLANK_AT_EOL;
167 else
168 break;
172 if (trailing_whitespace == -1)
173 trailing_whitespace = len;
175 /* Check indentation */
176 for (i = 0; i < trailing_whitespace; i++) {
177 if (line[i] == ' ')
178 continue;
179 if (line[i] != '\t')
180 break;
181 if ((ws_rule & WS_SPACE_BEFORE_TAB) && written < i) {
182 result |= WS_SPACE_BEFORE_TAB;
183 if (stream) {
184 fputs(ws, stream);
185 fwrite(line + written, i - written, 1, stream);
186 fputs(reset, stream);
187 fwrite(line + i, 1, 1, stream);
189 } else if (ws_rule & WS_TAB_IN_INDENT) {
190 result |= WS_TAB_IN_INDENT;
191 if (stream) {
192 fwrite(line + written, i - written, 1, stream);
193 fputs(ws, stream);
194 fwrite(line + i, 1, 1, stream);
195 fputs(reset, stream);
197 } else if (stream) {
198 fwrite(line + written, i - written + 1, 1, stream);
200 written = i + 1;
203 /* Check for indent using non-tab. */
204 if ((ws_rule & WS_INDENT_WITH_NON_TAB) && i - written >= ws_tab_width(ws_rule)) {
205 result |= WS_INDENT_WITH_NON_TAB;
206 if (stream) {
207 fputs(ws, stream);
208 fwrite(line + written, i - written, 1, stream);
209 fputs(reset, stream);
211 written = i;
214 if (stream) {
216 * Now the rest of the line starts at "written".
217 * The non-highlighted part ends at "trailing_whitespace".
220 /* Emit non-highlighted (middle) segment. */
221 if (trailing_whitespace - written > 0) {
222 fputs(set, stream);
223 fwrite(line + written,
224 trailing_whitespace - written, 1, stream);
225 fputs(reset, stream);
228 /* Highlight errors in trailing whitespace. */
229 if (trailing_whitespace != len) {
230 fputs(ws, stream);
231 fwrite(line + trailing_whitespace,
232 len - trailing_whitespace, 1, stream);
233 fputs(reset, stream);
235 if (trailing_carriage_return)
236 fputc('\r', stream);
237 if (trailing_newline)
238 fputc('\n', stream);
240 return result;
243 void ws_check_emit(const char *line, int len, unsigned ws_rule,
244 FILE *stream, const char *set,
245 const char *reset, const char *ws)
247 (void)ws_check_emit_1(line, len, ws_rule, stream, set, reset, ws);
250 unsigned ws_check(const char *line, int len, unsigned ws_rule)
252 return ws_check_emit_1(line, len, ws_rule, NULL, NULL, NULL, NULL);
255 int ws_blank_line(const char *line, int len, unsigned ws_rule)
258 * We _might_ want to treat CR differently from other
259 * whitespace characters when ws_rule has WS_CR_AT_EOL, but
260 * for now we just use this stupid definition.
262 while (len-- > 0) {
263 if (!isspace(*line))
264 return 0;
265 line++;
267 return 1;
270 /* Copy the line onto the end of the strbuf while fixing whitespaces */
271 void ws_fix_copy(struct strbuf *dst, const char *src, int len, unsigned ws_rule, int *error_count)
274 * len is number of bytes to be copied from src, starting
275 * at src. Typically src[len-1] is '\n', unless this is
276 * the incomplete last line.
278 int i;
279 int add_nl_to_tail = 0;
280 int add_cr_to_tail = 0;
281 int fixed = 0;
282 int last_tab_in_indent = -1;
283 int last_space_in_indent = -1;
284 int need_fix_leading_space = 0;
287 * Strip trailing whitespace
289 if (ws_rule & WS_BLANK_AT_EOL) {
290 if (0 < len && src[len - 1] == '\n') {
291 add_nl_to_tail = 1;
292 len--;
293 if (0 < len && src[len - 1] == '\r') {
294 add_cr_to_tail = !!(ws_rule & WS_CR_AT_EOL);
295 len--;
298 if (0 < len && isspace(src[len - 1])) {
299 while (0 < len && isspace(src[len-1]))
300 len--;
301 fixed = 1;
306 * Check leading whitespaces (indent)
308 for (i = 0; i < len; i++) {
309 char ch = src[i];
310 if (ch == '\t') {
311 last_tab_in_indent = i;
312 if ((ws_rule & WS_SPACE_BEFORE_TAB) &&
313 0 <= last_space_in_indent)
314 need_fix_leading_space = 1;
315 } else if (ch == ' ') {
316 last_space_in_indent = i;
317 if ((ws_rule & WS_INDENT_WITH_NON_TAB) &&
318 ws_tab_width(ws_rule) <= i - last_tab_in_indent)
319 need_fix_leading_space = 1;
320 } else
321 break;
324 if (need_fix_leading_space) {
325 /* Process indent ourselves */
326 int consecutive_spaces = 0;
327 int last = last_tab_in_indent + 1;
329 if (ws_rule & WS_INDENT_WITH_NON_TAB) {
330 /* have "last" point at one past the indent */
331 if (last_tab_in_indent < last_space_in_indent)
332 last = last_space_in_indent + 1;
333 else
334 last = last_tab_in_indent + 1;
338 * between src[0..last-1], strip the funny spaces,
339 * updating them to tab as needed.
341 for (i = 0; i < last; i++) {
342 char ch = src[i];
343 if (ch != ' ') {
344 consecutive_spaces = 0;
345 strbuf_addch(dst, ch);
346 } else {
347 consecutive_spaces++;
348 if (consecutive_spaces == ws_tab_width(ws_rule)) {
349 strbuf_addch(dst, '\t');
350 consecutive_spaces = 0;
354 while (0 < consecutive_spaces--)
355 strbuf_addch(dst, ' ');
356 len -= last;
357 src += last;
358 fixed = 1;
359 } else if ((ws_rule & WS_TAB_IN_INDENT) && last_tab_in_indent >= 0) {
360 /* Expand tabs into spaces */
361 int start = dst->len;
362 int last = last_tab_in_indent + 1;
363 for (i = 0; i < last; i++) {
364 if (src[i] == '\t')
365 do {
366 strbuf_addch(dst, ' ');
367 } while ((dst->len - start) % ws_tab_width(ws_rule));
368 else
369 strbuf_addch(dst, src[i]);
371 len -= last;
372 src += last;
373 fixed = 1;
376 strbuf_add(dst, src, len);
377 if (add_cr_to_tail)
378 strbuf_addch(dst, '\r');
379 if (add_nl_to_tail)
380 strbuf_addch(dst, '\n');
381 if (fixed && error_count)
382 (*error_count)++;