libs/rfc822/rfc822hdr.c

   1 /*
   2 ** Copyright 2001-2011 Double Precision, Inc.
   3 ** See COPYING for distribution information.
   4 */
   5
   6 #include        "config.h"
   7 #include        <stdio.h>
   8 #include        <ctype.h>
   9 #include        <stdlib.h>
  10 #include        <string.h>
  11 #include        "rfc822hdr.h"
  12
  13
  14 /*
  15 ** Read the next mail header.
  16 */
  17
  18 int rfc822hdr_read(struct rfc822hdr *h, FILE *f, off_t *pos, off_t epos)
  19 {
  20         size_t n=0;
  21         int c;
  22
  23         for (;;)
  24         {
  25                 if ( n >= h->hdrsize)
  26                 {
  27                         size_t hn=h->hdrsize + 1024;
  28                         char *p= h->header ? realloc(h->header, hn):
  29                                 malloc(hn);
  30
  31                         if (!p)
  32                                 return (-1);
  33
  34                         h->header=p;
  35                         h->hdrsize=hn;
  36                 }
  37
  38                 if (pos && *pos >= epos)
  39                 {
  40                         h->header[n]=0;
  41                         break;
  42                 }
  43
  44                 c=getc(f);
  45                 if (c == EOF)
  46                 {
  47                         if (pos)
  48                                 *pos=epos;
  49                         h->header[n]=0;
  50                         break;
  51                 }
  52                 if (pos)
  53                         ++*pos;
  54
  55                 h->header[n]=c;
  56                 if (c == '\n')
  57                 {
  58                         if (n == 0)
  59                         {
  60                                 if (pos)
  61                                         *pos=epos;
  62                                 h->header[n]=0;
  63                                 break;
  64                         }
  65
  66                         c=getc(f);
  67                         if (c != EOF)
  68                                 ungetc(c, f);
  69                         if (c == '\n' || c == '\r' ||
  70                             !isspace((int)(unsigned char)c))
  71                         {
  72                                 h->header[n]=0;
  73                                 break;
  74                         }
  75                 }
  76                 n++;
  77                 if (h->maxsize && n + 2 > h->maxsize)
  78                         --n;
  79         }
  80
  81         if (n == 0)
  82         {
  83                 if (pos)
  84                         *pos=epos;
  85                 h->value=h->header;
  86                 return (1);
  87         }
  88
  89         for (h->value=h->header; *h->value; ++h->value)
  90         {
  91                 if (*h->value == ':')
  92                 {
  93                         *h->value++=0;
  94                         while (*h->value &&
  95                                isspace((int)(unsigned char)*h->value))
  96                                 ++h->value;
  97                         break;
  98                 }
  99         }
 100         return (0);
 101 }
 102
 103 void rfc822hdr_fixname(struct rfc822hdr *h)
 104 {
 105         char *p;
 106
 107         for (p=h->header; *p; p++)
 108         {
 109                 *p=tolower((int)(unsigned char)*p);
 110         }
 111 }
 112
 113 void rfc822hdr_collapse(struct rfc822hdr *h)
 114 {
 115         char *p, *q;
 116
 117         for (p=q=h->value; *p; )
 118         {
 119                 if (*p == '\n')
 120                 {
 121                         while (*p && isspace((int)(unsigned char)*p))
 122                                 ++p;
 123                         *q++=' ';
 124                         continue;
 125                 }
 126                 *q++ = *p++;
 127         }
 128         *q=0;
 129 }
 130
 131 /* This is, basically, a case-insensitive US-ASCII comparison function */
 132
 133 #define lc(x) ((x) >= 'A' && (x) <= 'Z' ? (x) + ('a'-'A'):(x))
 134
 135 int rfc822hdr_namecmp(const char *a, const char *b)
 136 {
 137         int rc;
 138
 139         while ((rc=(int)(unsigned char)lc(*a) - (int)(unsigned char)lc(*b))==0)
 140         {
 141                 if (!*a)
 142                         return 0;
 143                 ++a;
 144                 ++b;
 145         }
 146
 147         return rc;
 148 }
 149
 150 int rfc822hdr_is_addr(const char *hdr)
 151 {
 152         return rfc822hdr_namecmp(hdr, "from") == 0 ||
 153                 rfc822hdr_namecmp(hdr, "to") == 0 ||
 154                 rfc822hdr_namecmp(hdr, "cc") == 0 ||
 155                 rfc822hdr_namecmp(hdr, "bcc") == 0 ||
 156                 rfc822hdr_namecmp(hdr, "resent-from") == 0 ||
 157                 rfc822hdr_namecmp(hdr, "resent-to") == 0 ||
 158                 rfc822hdr_namecmp(hdr, "resent-cc") == 0 ||
 159                 rfc822hdr_namecmp(hdr, "resent-bcc") == 0;
 160 }