mbox.c

   1 #include <ctype.h>
   2 #include <errno.h>
   3 #include <fcntl.h>
   4 #include <stdlib.h>
   5 #include <string.h>
   6 #include <strings.h>
   7 #include <unistd.h>
   8 #include <utime.h>
   9 #include <sys/types.h>
  10 #include <sys/stat.h>
  11 #include "mbox.h"
  12 #include "util.h"
  13
  14 #define INCSIZE         (1 << 21)
  15
  16 static void set_atime(char *filename)
  17 {
  18         struct stat st;
  19         struct utimbuf times;
  20         stat(filename, &st);
  21         times.actime = time(NULL);
  22         times.modtime = st.st_mtime;
  23         utime(filename, &times);
  24 }
  25
  26 static char *mail_start(char *r)
  27 {
  28         char *s = r;
  29         while (s) {
  30                 if (!strncmp("From ", s, 5) && (s == r || *(s - 1) == '\n'))
  31                         break;
  32                 s = strchr(s + 1, 'F');
  33         }
  34         return s;
  35 }
  36
  37 static char *mail_hdrs(struct mail *mail, char *s)
  38 {
  39         static char stat[] = "Status:";
  40         while (s && *s && *s != '\r' && *s != '\n') {
  41                 if (isalpha(*s) && mail->nhdrs < MAXHDRS)
  42                         mail->hdrs[mail->nhdrs++] = s;
  43                 if (!strncasecmp(stat, s, sizeof(stat) - 1))
  44                         mail->stat_hdr = s;
  45                 s = strchr(s + 1, '\n');
  46                 s = s ? s + 1 : s;
  47         }
  48         mail->hdrs[mail->nhdrs] = s;
  49         return s;
  50 }
  51
  52 char *mail_hdr(struct mail *mail, char *hdr)
  53 {
  54         int i;
  55         int len = strlen(hdr);
  56         for (i = 0; i < mail->nhdrs; i++)
  57                 if (!strncasecmp(mail->hdrs[i], hdr, len))
  58                         return mail->hdrs[i];
  59         return NULL;
  60 }
  61
  62 int hdr_len(char *hdr)
  63 {
  64         char *s = hdr;
  65         while (*s) {
  66                 char *r = strchr(s, '\n');
  67                 if (!r)
  68                         return strchr(s, '\0') - hdr;
  69                 s = r;
  70                 if (!isspace(*(s + 1)))
  71                         return s - hdr;
  72                 s++;
  73         }
  74         return 0;
  75 }
  76
  77 static void mail_stat(struct mail *mail)
  78 {
  79         if (mail->stat_hdr) {
  80                 char *s = mail->stat_hdr + strlen("Status:");
  81                 while (*s && *s != '\r' && *s != '\n') {
  82                         switch (*s++) {
  83                         case 'O':
  84                                 mail->stat |= STAT_OLD;
  85                                 break;
  86                         case 'N':
  87                                 mail->stat |= STAT_NEW;
  88                                 break;
  89                         case 'R':
  90                                 mail->stat |= STAT_READ;
  91                                 break;
  92                         }
  93                 }
  94                 mail->orig_stat = mail->stat;
  95         } else {
  96                 mail->stat = STAT_NEW;
  97         }
  98 }
  99
 100 static char *mail_read(struct mail *mail, char *s)
 101 {
 102         char *end;
 103         int last = 0;
 104         mail->head = s;
 105         mail->body = mail_hdrs(mail, s);
 106         if (!(end = mail_start(mail->body))) {
 107                 last = 1;
 108                 end = strchr(mail->body, '\0');
 109         }
 110         mail->len = end - mail->head;
 111         mail->body_len = end - mail->body;
 112         mail_stat(mail);
 113         return last ? NULL : end;
 114 }
 115
 116 static void read_mails(struct mbox *mbox, char *s)
 117 {
 118         while (s)
 119                 s = mail_read(&mbox->mails[mbox->n++], s);
 120 }
 121
 122 int mbox_inc(struct mbox *mbox)
 123 {
 124         int fd = open(mbox->path, O_RDONLY | O_LARGEFILE);
 125         int old_n = mbox->n;
 126         int old_len = mbox->len;
 127         int len = file_size(fd);
 128         if (fd == -1)
 129                 return 0;
 130         if (!mbox->mbox) {
 131                 mbox->size = len + INCSIZE + 1;
 132                 mbox->mbox = malloc(mbox->size);
 133         }
 134         if (len > mbox->size - 1)
 135                 return -1;
 136         if (mbox->len)
 137                 lseek(fd, mbox->len, SEEK_SET);
 138         mbox->len += xread(fd, mbox->mbox + mbox->len, len);
 139         mbox->mbox[mbox->len] = '\0';
 140         close(fd);
 141         set_atime(mbox->path);
 142         if (old_len < mbox->len)
 143                 read_mails(mbox, mbox->mbox + old_len);
 144         return mbox->n - old_n;
 145 }
 146
 147 struct mbox *mbox_alloc(char *filename)
 148 {
 149         struct mbox *mbox;
 150         mbox = malloc(sizeof(*mbox));
 151         memset(mbox, 0, sizeof(*mbox));
 152         strcpy(mbox->path, filename);
 153         mbox_inc(mbox);
 154         return mbox;
 155 }
 156
 157 void mbox_free(struct mbox *mbox)
 158 {
 159         free(mbox->mbox);
 160         free(mbox);
 161 }
 162
 163 int mail_head(struct mail *mail, char *buf, int buf_len,
 164                 char **hdrs, int n)
 165 {
 166         int i, j;
 167         char *s = buf;
 168         char *dead = s + buf_len;
 169         for (i = 0; i < n; i++) {
 170                 char *pat = hdrs[i];
 171                 int pat_len = strlen(hdrs[i]);
 172                 for (j = 0; j < mail->nhdrs; j++) {
 173                         char *hdr = mail->hdrs[j];
 174                         if (!strncasecmp(hdr, pat, pat_len)) {
 175                                 int hdr_len = mail->hdrs[j + 1] - hdr;
 176                                 if (s + hdr_len > dead)
 177                                         hdr_len = dead - s;
 178                                 memcpy(s, hdr, hdr_len);
 179                                 s += hdr_len;
 180                                 break;
 181                         }
 182                 }
 183         }
 184         *s = '\0';
 185         return s - buf;
 186 }
 187
 188 static int mail_changed(struct mail *mail)
 189 {
 190         return mail->orig_stat != mail->stat;
 191 }
 192
 193 void mail_write(struct mail *mail, int fd)
 194 {
 195         char stat[32] = "Status: ";
 196         char *s = strchr(stat, '\0');
 197         if (mail->stat & STAT_READ)
 198                 *s++ = 'R';
 199         *s++ = 'O';
 200         *s++ = '\n';
 201         if (!mail->stat_hdr) {
 202                 xwrite(fd, mail->head, mail->body - mail->head);
 203                 write(fd, stat, s - stat);
 204                 write(fd, mail->body, mail->body_len);
 205         } else {
 206                 char *hdr_end = strchr(mail->stat_hdr, '\n');
 207                 xwrite(fd, mail->head, mail->stat_hdr - mail->head);
 208                 write(fd, stat, s - stat);
 209                 if (hdr_end)
 210                         write(fd, hdr_end + 1,
 211                                 mail->head + mail->len - hdr_end - 1);
 212         }
 213 }
 214
 215 static int mbox_changed(struct mbox *mbox)
 216 {
 217         int i;
 218         for (i = 0; i < mbox->n; i++)
 219                 if (mail_changed(&mbox->mails[i]))
 220                         return 1;
 221         return 0;
 222 }
 223
 224 int mbox_write(struct mbox *mbox)
 225 {
 226         int fd;
 227         int i = 0;
 228         if (mbox_inc(mbox) == -1)
 229                 return -1;
 230         if (!mbox_changed(mbox))
 231                 return 0;
 232         fd = open(mbox->path, O_WRONLY | O_CREAT, S_IRUSR | S_IWUSR);
 233         while (i < mbox->n) {
 234                 char *beg = mbox->mails[i].head;
 235                 char *end = mbox->mbox + mbox->len;
 236                 while (i < mbox->n && !mail_changed(&mbox->mails[i]))
 237                         i++;
 238                 if (i < mbox->n)
 239                         end = mbox->mails[i].head;
 240                 xwrite(fd, beg, end - beg);
 241                 if (i < mbox->n)
 242                         mail_write(&mbox->mails[i++], fd);
 243         }
 244         close(fd);
 245         return 0;
 246 }