html.c

   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!$()*,./:;@- */
  17 static 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
  42 int htmlfd = STDOUT_FILENO;
  43
  44 char *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
  64 void html_raw(const char *data, size_t size)
  65 {
  66         write(htmlfd, data, size);
  67 }
  68
  69 void html(const char *txt)
  70 {
  71         write(htmlfd, txt, strlen(txt));
  72 }
  73
  74 void htmlf(const char *format, ...)
  75 {
  76         static char buf[65536];
  77         va_list args;
  78
  79         va_start(args, format);
  80         vsnprintf(buf, sizeof(buf), format, args);
  81         va_end(args);
  82         html(buf);
  83 }
  84
  85 void html_status(int code, const char *msg, int more_headers)
  86 {
  87         htmlf("Status: %d %s\n", code, msg);
  88         if (!more_headers)
  89                 html("\n");
  90 }
  91
  92 void html_txt(const char *txt)
  93 {
  94         const char *t = txt;
  95         while(t && *t){
  96                 int c = *t;
  97                 if (c=='<' || c=='>' || c=='&') {
  98                         html_raw(txt, t - txt);
  99                         if (c=='>')
 100                                 html("&gt;");
 101                         else if (c=='<')
 102                                 html("&lt;");
 103                         else if (c=='&')
 104                                 html("&amp;");
 105                         txt = t+1;
 106                 }
 107                 t++;
 108         }
 109         if (t!=txt)
 110                 html(txt);
 111 }
 112
 113 void html_ntxt(int len, const char *txt)
 114 {
 115         const char *t = txt;
 116         while(t && *t && len--){
 117                 int c = *t;
 118                 if (c=='<' || c=='>' || c=='&') {
 119                         html_raw(txt, t - txt);
 120                         if (c=='>')
 121                                 html("&gt;");
 122                         else if (c=='<')
 123                                 html("&lt;");
 124                         else if (c=='&')
 125                                 html("&amp;");
 126                         txt = t+1;
 127                 }
 128                 t++;
 129         }
 130         if (t!=txt)
 131                 html_raw(txt, t - txt);
 132         if (len<0)
 133                 html("...");
 134 }
 135
 136 void html_attr(const char *txt)
 137 {
 138         const char *t = txt;
 139         while(t && *t){
 140                 int c = *t;
 141                 if (c=='<' || c=='>' || c=='\'' || c=='\"' || c=='&') {
 142                         html_raw(txt, t - txt);
 143                         if (c=='>')
 144                                 html("&gt;");
 145                         else if (c=='<')
 146                                 html("&lt;");
 147                         else if (c=='\'')
 148                                 html("&#x27;");
 149                         else if (c=='"')
 150                                 html("&quot;");
 151                         else if (c=='&')
 152                                 html("&amp;");
 153                         txt = t+1;
 154                 }
 155                 t++;
 156         }
 157         if (t!=txt)
 158                 html(txt);
 159 }
 160
 161 void html_url_path(const char *txt)
 162 {
 163         const char *t = txt;
 164         while(t && *t){
 165                 unsigned char c = *t;
 166                 const char *e = url_escape_table[c];
 167                 if (e && c!='+' && c!='&') {
 168                         html_raw(txt, t - txt);
 169                         html(e);
 170                         txt = t+1;
 171                 }
 172                 t++;
 173         }
 174         if (t!=txt)
 175                 html(txt);
 176 }
 177
 178 void html_url_arg(const char *txt)
 179 {
 180         const char *t = txt;
 181         while(t && *t){
 182                 unsigned char c = *t;
 183                 const char *e = url_escape_table[c];
 184                 if (c == ' ')
 185                         e = "+";
 186                 if (e) {
 187                         html_raw(txt, t - txt);
 188                         html(e);
 189                         txt = t+1;
 190                 }
 191                 t++;
 192         }
 193         if (t!=txt)
 194                 html(txt);
 195 }
 196
 197 void html_hidden(const char *name, const char *value)
 198 {
 199         html("<input type='hidden' name='");
 200         html_attr(name);
 201         html("' value='");
 202         html_attr(value);
 203         html("'/>");
 204 }
 205
 206 void html_option(const char *value, const char *text, const char *selected_value)
 207 {
 208         html("<option value='");
 209         html_attr(value);
 210         html("'");
 211         if (selected_value && !strcmp(selected_value, value))
 212                 html(" selected='selected'");
 213         html(">");
 214         html_txt(text);
 215         html("</option>\n");
 216 }
 217
 218 void html_intoption(int value, const char *text, int selected_value)
 219 {
 220         htmlf("<option value='%d'%s>", value,
 221               value == selected_value ? " selected='selected'" : "");
 222         html_txt(text);
 223         html("</option>");
 224 }
 225
 226 void html_link_open(const char *url, const char *title, const char *class)
 227 {
 228         html("<a href='");
 229         html_attr(url);
 230         if (title) {
 231                 html("' title='");
 232                 html_attr(title);
 233         }
 234         if (class) {
 235                 html("' class='");
 236                 html_attr(class);
 237         }
 238         html("'>");
 239 }
 240
 241 void html_link_close(void)
 242 {
 243         html("</a>");
 244 }
 245
 246 void html_fileperm(unsigned short mode)
 247 {
 248         htmlf("%c%c%c", (mode & 4 ? 'r' : '-'),
 249               (mode & 2 ? 'w' : '-'), (mode & 1 ? 'x' : '-'));
 250 }
 251
 252 int html_include(const char *filename)
 253 {
 254         FILE *f;
 255         char buf[4096];
 256         size_t len;
 257
 258         if (!(f = fopen(filename, "r"))) {
 259                 fprintf(stderr, "[cgit] Failed to include file %s: %s (%d).\n",
 260                         filename, strerror(errno), errno);
 261                 return -1;
 262         }
 263         while((len = fread(buf, 1, 4096, f)) > 0)
 264                 html_raw(buf, len);
 265         fclose(f);
 266         return 0;
 267 }
 268
 269 int hextoint(char c)
 270 {
 271         if (c >= 'a' && c <= 'f')
 272                 return 10 + c - 'a';
 273         else if (c >= 'A' && c <= 'F')
 274                 return 10 + c - 'A';
 275         else if (c >= '0' && c <= '9')
 276                 return c - '0';
 277         else
 278                 return -1;
 279 }
 280
 281 char *convert_query_hexchar(char *txt)
 282 {
 283         int d1, d2, n;
 284         n = strlen(txt);
 285         if (n < 3) {
 286                 *txt = '\0';
 287                 return txt-1;
 288         }
 289         d1 = hextoint(*(txt+1));
 290         d2 = hextoint(*(txt+2));
 291         if (d1<0 || d2<0) {
 292                 memmove(txt, txt+3, n-2);
 293                 return txt-1;
 294         } else {
 295                 *txt = d1 * 16 + d2;
 296                 memmove(txt+1, txt+3, n-2);
 297                 return txt;
 298         }
 299 }
 300
 301 int http_parse_querystring(const char *txt_, void (*fn)(const char *name, const char *value))
 302 {
 303         char *o, *t, *txt, *value = NULL, c;
 304
 305         if (!txt_)
 306                 return 0;
 307
 308         o = t = txt = strdup(txt_);
 309         if (t == NULL) {
 310                 printf("Out of memory\n");
 311                 exit(1);
 312         }
 313         while((c=*t) != '\0') {
 314                 if (c=='=') {
 315                         *t = '\0';
 316                         value = t+1;
 317                 } else if (c=='+') {
 318                         *t = ' ';
 319                 } else if (c=='%') {
 320                         t = convert_query_hexchar(t);
 321                 } else if (c=='&') {
 322                         *t = '\0';
 323                         (*fn)(txt, value);
 324                         txt = t+1;
 325                         value = NULL;
 326                 }
 327                 t++;
 328         }
 329         if (t!=txt)
 330                 (*fn)(txt, value);
 331         free(o);
 332         return 0;
 333 }