headers.c

   1 #include <assert.h>
   2 #include <string.h>
   3 #include <event2/buffer.h>
   4
   5 #include "util.h"
   6 #include "headers.h"
   7
   8 void
   9 headers_add_key(struct header_list *headers, const char *key, size_t n)
  10 {
  11         struct header *h;
  12
  13         h = mem_calloc(1, sizeof(*h) + n + 1);
  14         TAILQ_INIT(&h->val);
  15         memcpy(h->key, key, n);
  16         TAILQ_INSERT_TAIL(headers, h, next);
  17 }
  18
  19 void
  20 headers_add_val(struct header_list *headers, const char *val, size_t n)
  21 {
  22         struct header *h;
  23         struct val_line *line;
  24
  25         h = TAILQ_LAST(headers, header_list);
  26         assert(h != NULL);
  27
  28         line = mem_calloc(1, sizeof(*line) + n + 1);
  29         memcpy(line->str, val, n);
  30         line->len = n;
  31         TAILQ_INSERT_TAIL(&h->val, line, next);
  32         h->val_len += n;
  33 }
  34
  35 void
  36 headers_dump(struct header_list *headers, struct evbuffer *buf)
  37 {
  38         struct header *h;
  39         struct val_line *line;
  40
  41         TAILQ_FOREACH(h, headers, next) {
  42                 evbuffer_add_printf(buf, "%s:", h->key);
  43                 TAILQ_FOREACH(line, &h->val, next)
  44                         evbuffer_add_printf(buf, "%s\r\n", line->str);
  45         }
  46
  47         evbuffer_add(buf, "\r\n", 2);
  48 }
  49
  50 /* return: -1 error, 0 need more data, 1 finished. */
  51 int
  52 headers_parse(struct header_list *headers, struct evbuffer *buf)
  53 {
  54         char *line, *p;
  55
  56         while ((line = evbuffer_readln(buf, NULL, EVBUFFER_EOL_CRLF))) {
  57                 if (*line == '\0') {
  58                         mem_free(line);
  59                         return 1;
  60                 }
  61
  62                 p = line;
  63
  64                 if (*line != ' ' && *line != '\t') {
  65                         p = strchr(line, ':');
  66                         if (!p) {
  67                                 mem_free(line);
  68                                 return -1;
  69                         }
  70                         headers_add_key(headers, line, p - line);
  71                         ++p;
  72                 }
  73
  74                 if (!TAILQ_LAST(headers, header_list)) {
  75                         mem_free(line);
  76                         return -1;
  77                 }
  78
  79                 headers_add_val(headers, p, strlen(p));
  80                 mem_free(line);
  81         }
  82
  83         return 0;
  84 }
  85
  86 /* caller must free result; returns NULL if key not found. */
  87 char *
  88 headers_find(struct header_list *headers, const char *key)
  89 {
  90         struct header *h;
  91         struct val_line *line;
  92         char *ret, *p;
  93         size_t len;
  94
  95         TAILQ_FOREACH(h, headers, next) {
  96                 if (evutil_ascii_strcasecmp(h->key, key))
  97                         continue;
  98
  99                 /* calculate total size */
 100                 TAILQ_FOREACH(line, &h->val, next)
 101                         len += line->len;
 102
 103                 /* XXX Some of this space is wasted if we trim any leading WS
 104                    from value lines */
 105                 ret = mem_calloc(1, len + 1);
 106                 p = ret;
 107
 108                 TAILQ_FOREACH(line, &h->val, next) {
 109                         len = strspn(line->str, " \t");
 110                         /* after the first line, translate leading WS to
 111                            a single SP */
 112                         if (p != ret)
 113                                 *p++ = ' ';
 114                         memcpy(p, line->str + len, line->len - len);
 115                         p += line->len - len;
 116                 }
 117
 118                 return ret;
 119         }
 120
 121         return NULL;
 122 }
 123
 124 void
 125 headers_clear(struct header_list *headers)
 126 {
 127         struct header *h;
 128         struct val_line *line;
 129
 130         while ((h = TAILQ_FIRST(headers))) {
 131                 TAILQ_REMOVE(headers, h, next);
 132                 while ((line = TAILQ_FIRST(&h->val))) {
 133                         TAILQ_REMOVE(&h->val, line, next);
 134                         mem_free(line);
 135                 }
 136                 mem_free(h);
 137         }
 138 }
 139
 140 #ifdef TEST_HEADERS
 141 #include <stdio.h>
 142 int main(int argc, char **argv)
 143 {
 144         struct evbuffer *buf, *buf2;
 145         struct header_list headers;
 146         char line[256];
 147
 148         buf = evbuffer_new();
 149         buf2 = evbuffer_new();
 150         TAILQ_INIT(&headers);
 151
 152         while (fgets(line, sizeof(line), stdin)) {
 153                 evbuffer_add(buf, line, strlen(line));
 154         }
 155
 156         headers_parse(&headers, buf);
 157         headers_dump(&headers, buf2);
 158
 159         printf("buf1..\n");
 160         fwrite(evbuffer_pullup(buf, evbuffer_get_length(buf)), evbuffer_get_length(buf), 1, stdout);
 161         printf("\nbuf2..\n");
 162         fwrite(evbuffer_pullup(buf2, evbuffer_get_length(buf2)), evbuffer_get_length(buf2), 1, stdout);
 163
 164         if (argc > 1) {
 165                 int i;
 166                 printf("\nfinding stuffs...\n");
 167                 for (i = 1; i < argc; ++i) {
 168                         char *buf = headers_find(&headers, argv[i]);
 169                         printf("%s? %s\n", argv[i], buf? buf : "NOT FOUND");
 170                         if (buf) mem_free(buf);
 171                 }
 172         }
 173
 174         evbuffer_free(buf);
 175         evbuffer_free(buf2);
 176
 177         return 0;
 178 }
 179 #endif