1/* html.c: helper functions for html output
  2 *
  3 * Copyright (C) 2006 Lars Hjemli
  4 *
  5 * Licensed under GNU General Public License v2
  6 *   (see COPYING for full license text)
  7 */
  8
  9#include <unistd.h>
 10#include <stdio.h>
 11#include <stdlib.h>
 12#include <stdarg.h>
 13#include <string.h>
 14#include <errno.h>
 15
 16/* Percent-encoding of each character, except: a-zA-Z0-9!$()*,./:;@- */
 17static const char* url_escape_table[256] = {
 18	"%00", "%01", "%02", "%03", "%04", "%05", "%06", "%07", "%08", "%09",
 19	"%0a", "%0b", "%0c", "%0d", "%0e", "%0f", "%10", "%11", "%12", "%13",
 20	"%14", "%15", "%16", "%17", "%18", "%19", "%1a", "%1b", "%1c", "%1d",
 21	"%1e", "%1f", "%20", 0, "%22", "%23", 0, "%25", "%26", "%27", 0, 0, 0,
 22	"%2b", 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, "%3c", "%3d",
 23	"%3e", "%3f", 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 24	0, 0, 0, 0, 0, 0, 0, 0, 0, "%5c", 0, "%5e", 0, "%60", 0, 0, 0, 0, 0,
 25	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, "%7b",
 26	"%7c", "%7d", 0, "%7f", "%80", "%81", "%82", "%83", "%84", "%85",
 27	"%86", "%87", "%88", "%89", "%8a", "%8b", "%8c", "%8d", "%8e", "%8f",
 28	"%90", "%91", "%92", "%93", "%94", "%95", "%96", "%97", "%98", "%99",
 29	"%9a", "%9b", "%9c", "%9d", "%9e", "%9f", "%a0", "%a1", "%a2", "%a3",
 30	"%a4", "%a5", "%a6", "%a7", "%a8", "%a9", "%aa", "%ab", "%ac", "%ad",
 31	"%ae", "%af", "%b0", "%b1", "%b2", "%b3", "%b4", "%b5", "%b6", "%b7",
 32	"%b8", "%b9", "%ba", "%bb", "%bc", "%bd", "%be", "%bf", "%c0", "%c1",
 33	"%c2", "%c3", "%c4", "%c5", "%c6", "%c7", "%c8", "%c9", "%ca", "%cb",
 34	"%cc", "%cd", "%ce", "%cf", "%d0", "%d1", "%d2", "%d3", "%d4", "%d5",
 35	"%d6", "%d7", "%d8", "%d9", "%da", "%db", "%dc", "%dd", "%de", "%df",
 36	"%e0", "%e1", "%e2", "%e3", "%e4", "%e5", "%e6", "%e7", "%e8", "%e9",
 37	"%ea", "%eb", "%ec", "%ed", "%ee", "%ef", "%f0", "%f1", "%f2", "%f3",
 38	"%f4", "%f5", "%f6", "%f7", "%f8", "%f9", "%fa", "%fb", "%fc", "%fd",
 39	"%fe", "%ff"
 40};
 41
 42static int htmlfd = STDOUT_FILENO;
 43
 44char *fmt(const char *format, ...)
 45{
 46	static char buf[8][1024];
 47	static int bufidx;
 48	int len;
 49	va_list args;
 50
 51	bufidx++;
 52	bufidx &= 7;
 53
 54	va_start(args, format);
 55	len = vsnprintf(buf[bufidx], sizeof(buf[bufidx]), format, args);
 56	va_end(args);
 57	if (len > sizeof(buf[bufidx])) {
 58		fprintf(stderr, "[html.c] string truncated: %s\n", format);
 59		exit(1);
 60	}
 61	return buf[bufidx];
 62}
 63
 64void html_raw(const char *data, size_t size)
 65{
 66	if (write(htmlfd, data, size) != size)
 67		fprintf(stderr, "[html.c] html output truncated.\n");
 68}
 69
 70void html(const char *txt)
 71{
 72	html_raw(txt, strlen(txt));
 73}
 74
 75void htmlf(const char *format, ...)
 76{
 77	static char buf[65536];
 78	va_list args;
 79
 80	va_start(args, format);
 81	vsnprintf(buf, sizeof(buf), format, args);
 82	va_end(args);
 83	html(buf);
 84}
 85
 86void html_status(int code, const char *msg, int more_headers)
 87{
 88	htmlf("Status: %d %s\n", code, msg);
 89	if (!more_headers)
 90		html("\n");
 91}
 92
 93void html_txt(const char *txt)
 94{
 95	const char *t = txt;
 96	while (t && *t) {
 97		int c = *t;
 98		if (c == '<' || c == '>' || c == '&') {
 99			html_raw(txt, t - txt);
100			if (c == '>')
101				html("&gt;");
102			else if (c == '<')
103				html("&lt;");
104			else if (c == '&')
105				html("&amp;");
106			txt = t + 1;
107		}
108		t++;
109	}
110	if (t != txt)
111		html(txt);
112}
113
114void html_ntxt(int len, const char *txt)
115{
116	const char *t = txt;
117	while (t && *t && len--) {
118		int c = *t;
119		if (c == '<' || c == '>' || c == '&') {
120			html_raw(txt, t - txt);
121			if (c == '>')
122				html("&gt;");
123			else if (c == '<')
124				html("&lt;");
125			else if (c == '&')
126				html("&amp;");
127			txt = t + 1;
128		}
129		t++;
130	}
131	if (t != txt)
132		html_raw(txt, t - txt);
133	if (len < 0)
134		html("...");
135}
136
137void html_attr(const char *txt)
138{
139	const char *t = txt;
140	while (t && *t) {
141		int c = *t;
142		if (c == '<' || c == '>' || c == '\'' || c == '\"' || c == '&') {
143			html_raw(txt, t - txt);
144			if (c == '>')
145				html("&gt;");
146			else if (c == '<')
147				html("&lt;");
148			else if (c == '\'')
149				html("&#x27;");
150			else if (c == '"')
151				html("&quot;");
152			else if (c == '&')
153				html("&amp;");
154			txt = t + 1;
155		}
156		t++;
157	}
158	if (t != txt)
159		html(txt);
160}
161
162void html_url_path(const char *txt)
163{
164	const char *t = txt;
165	while (t && *t) {
166		unsigned char c = *t;
167		const char *e = url_escape_table[c];
168		if (e && c != '+' && c != '&') {
169			html_raw(txt, t - txt);
170			html(e);
171			txt = t + 1;
172		}
173		t++;
174	}
175	if (t != txt)
176		html(txt);
177}
178
179void html_url_arg(const char *txt)
180{
181	const char *t = txt;
182	while (t && *t) {
183		unsigned char c = *t;
184		const char *e = url_escape_table[c];
185		if (c == ' ')
186			e = "+";
187		if (e) {
188			html_raw(txt, t - txt);
189			html(e);
190			txt = t + 1;
191		}
192		t++;
193	}
194	if (t != txt)
195		html(txt);
196}
197
198void html_hidden(const char *name, const char *value)
199{
200	html("<input type='hidden' name='");
201	html_attr(name);
202	html("' value='");
203	html_attr(value);
204	html("'/>");
205}
206
207void html_option(const char *value, const char *text, const char *selected_value)
208{
209	html("<option value='");
210	html_attr(value);
211	html("'");
212	if (selected_value && !strcmp(selected_value, value))
213		html(" selected='selected'");
214	html(">");
215	html_txt(text);
216	html("</option>\n");
217}
218
219void html_intoption(int value, const char *text, int selected_value)
220{
221	htmlf("<option value='%d'%s>", value,
222	      value == selected_value ? " selected='selected'" : "");
223	html_txt(text);
224	html("</option>");
225}
226
227void html_link_open(const char *url, const char *title, const char *class)
228{
229	html("<a href='");
230	html_attr(url);
231	if (title) {
232		html("' title='");
233		html_attr(title);
234	}
235	if (class) {
236		html("' class='");
237		html_attr(class);
238	}
239	html("'>");
240}
241
242void html_link_close(void)
243{
244	html("</a>");
245}
246
247void html_fileperm(unsigned short mode)
248{
249	htmlf("%c%c%c", (mode & 4 ? 'r' : '-'),
250	      (mode & 2 ? 'w' : '-'), (mode & 1 ? 'x' : '-'));
251}
252
253int html_include(const char *filename)
254{
255	FILE *f;
256	char buf[4096];
257	size_t len;
258
259	if (!(f = fopen(filename, "r"))) {
260		fprintf(stderr, "[cgit] Failed to include file %s: %s (%d).\n",
261			filename, strerror(errno), errno);
262		return -1;
263	}
264	while ((len = fread(buf, 1, 4096, f)) > 0)
265		html_raw(buf, len);
266	fclose(f);
267	return 0;
268}
269
270static int hextoint(char c)
271{
272	if (c >= 'a' && c <= 'f')
273		return 10 + c - 'a';
274	else if (c >= 'A' && c <= 'F')
275		return 10 + c - 'A';
276	else if (c >= '0' && c <= '9')
277		return c - '0';
278	else
279		return -1;
280}
281
282static char *convert_query_hexchar(char *txt)
283{
284	int d1, d2, n;
285	n = strlen(txt);
286	if (n < 3) {
287		*txt = '\0';
288		return txt-1;
289	}
290	d1 = hextoint(*(txt + 1));
291	d2 = hextoint(*(txt + 2));
292	if (d1 < 0 || d2 < 0) {
293		memmove(txt, txt + 3, n - 2);
294		return txt-1;
295	} else {
296		*txt = d1 * 16 + d2;
297		memmove(txt + 1, txt + 3, n - 2);
298		return txt;
299	}
300}
301
302int http_parse_querystring(const char *txt_, void (*fn)(const char *name, const char *value))
303{
304	char *o, *t, *txt, *value = NULL, c;
305
306	if (!txt_)
307		return 0;
308
309	o = t = txt = strdup(txt_);
310	if (t == NULL) {
311		printf("Out of memory\n");
312		exit(1);
313	}
314	while ((c=*t) != '\0') {
315		if (c == '=') {
316			*t = '\0';
317			value = t + 1;
318		} else if (c == '+') {
319			*t = ' ';
320		} else if (c == '%') {
321			t = convert_query_hexchar(t);
322		} else if (c == '&') {
323			*t = '\0';
324			(*fn)(txt, value);
325			txt = t + 1;
326			value = NULL;
327		}
328		t++;
329	}
330	if (t != txt)
331		(*fn)(txt, value);
332	free(o);
333	return 0;
334}