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         char *t;
  30         while (*s) {
  31                 if (!strncmp("From ", s, 5) && (s == r || *(s - 1) == '\n'))
  32                         break;
  33                 if ((t = strchr(s + 1, 'F')))
  34                         s = t;
  35                 else
  36                         s = strchr(s, '\0');
  37         }
  38         return s;
  39 }
  40
  41 static char *mail_hdrs(struct mail *mail, char *s)
  42 {
  43         static char stat[] = "Status:";
  44         char *r;
  45         while (s && *s && *s != '\r' && *s != '\n') {
  46                 if (isalpha(*s) && mail->nhdrs < MAXHDRS)
  47                         mail->hdrs[mail->nhdrs++] = s;
  48                 if (!strncasecmp(stat, s, sizeof(stat) - 1))
  49                         mail->stat_hdr = s;
  50                 if ((r = strchr(s + 1, '\n')))
  51                         s = r + 1;
  52                 else
  53                         s = strchr(s + 1, '\0');
  54         }
  55         mail->hdrs[mail->nhdrs] = s;
  56         return s;
  57 }
  58
  59 char *mail_hdr(struct mail *mail, char *hdr)
  60 {
  61         int i;
  62         int len = strlen(hdr);
  63         for (i = 1; i < mail->nhdrs; i++)
  64                 if (!strncasecmp(mail->hdrs[i], hdr, len))
  65                         return mail->hdrs[i];
  66         return NULL;
  67 }
  68
  69 int hdr_len(char *hdr)
  70 {
  71         char *s = hdr;
  72         while (*s) {
  73                 char *r = strchr(s, '\n');
  74                 if (!r)
  75                         return strchr(s, '\0') - hdr;
  76                 s = r;
  77                 if (!isspace(*(s + 1)))
  78                         return s - hdr;
  79                 s++;
  80         }
  81         return 0;
  82 }
  83
  84 static void mail_stat(struct mail *mail)
  85 {
  86         if (mail->stat_hdr) {
  87                 char *s = mail->stat_hdr + strlen("Status:");
  88                 while (*s && *s != '\r' && *s != '\n') {
  89                         switch (*s++) {
  90                         case 'O':
  91                                 mail->stat |= STAT_OLD;
  92                                 break;
  93                         case 'N':
  94                                 mail->stat |= STAT_NEW;
  95                                 break;
  96                         case 'R':
  97                                 mail->stat |= STAT_READ;
  98                                 break;
  99                         }
 100                 }
 101                 mail->orig_stat = mail->stat;
 102         } else {
 103                 mail->stat = STAT_NEW;
 104         }
 105 }
 106
 107 char *mail_read(struct mail *mail, char *s)
 108 {
 109         char *end;
 110         mail->head = s;
 111         mail->body = mail_hdrs(mail, s);
 112         end = mail_start(mail->body);
 113         mail->len = end - mail->head;
 114         mail->body_len = end - mail->body;
 115         mail_stat(mail);
 116         return end;
 117 }
 118
 119 static void read_mails(struct mbox *mbox, char *s)
 120 {
 121         while (s && *s)
 122                 s = mail_read(&mbox->mails[mbox->n++], s);
 123 }
 124
 125 int mbox_inc(struct mbox *mbox)
 126 {
 127         int fd = open(mbox->path, O_RDONLY | O_LARGEFILE);
 128         int old_n = mbox->n;
 129         int old_len = mbox->len;
 130         int len = file_size(fd);
 131         if (fd == -1)
 132                 return 0;
 133         if (!mbox->mbox) {
 134                 mbox->size = len + INCSIZE + 1;
 135                 mbox->mbox = malloc(mbox->size);
 136         }
 137         if (len > mbox->size - 1)
 138                 return -1;
 139         if (mbox->len)
 140                 lseek(fd, mbox->len, SEEK_SET);
 141         mbox->len += xread(fd, mbox->mbox + mbox->len, len);
 142         mbox->mbox[mbox->len] = '\0';
 143         close(fd);
 144         set_atime(mbox->path);
 145         if (old_len < mbox->len)
 146                 read_mails(mbox, mbox->mbox + old_len);
 147         return mbox->n - old_n;
 148 }
 149
 150 struct mbox *mbox_alloc(char *filename)
 151 {
 152         struct mbox *mbox;
 153         mbox = malloc(sizeof(*mbox));
 154         memset(mbox, 0, sizeof(*mbox));
 155         strcpy(mbox->path, filename);
 156         mbox_inc(mbox);
 157         return mbox;
 158 }
 159
 160 void mbox_free(struct mbox *mbox)
 161 {
 162         free(mbox->mbox);
 163         free(mbox);
 164 }
 165
 166 int mail_head(struct mail *mail, char *buf, int buf_len,
 167                 char **hdrs, int n)
 168 {
 169         int i, j;
 170         char *s = buf;
 171         char *dead = s + buf_len;
 172         for (i = 0; i < n; i++) {
 173                 char *pat = hdrs[i];
 174                 int pat_len = strlen(hdrs[i]);
 175                 for (j = 0; j < mail->nhdrs; j++) {
 176                         char *hdr = mail->hdrs[j];
 177                         if (!strncasecmp(hdr, pat, pat_len)) {
 178                                 int hdr_len = mail->hdrs[j + 1] - hdr;
 179                                 if (s + hdr_len > dead)
 180                                         hdr_len = dead - s;
 181                                 memcpy(s, hdr, hdr_len);
 182                                 s += hdr_len;
 183                                 break;
 184                         }
 185                 }
 186         }
 187         *s = '\0';
 188         return s - buf;
 189 }
 190
 191 static int mail_changed(struct mail *mail)
 192 {
 193         return mail->orig_stat != mail->stat;
 194 }
 195
 196 void mail_write(struct mail *mail, int fd)
 197 {
 198         char stat[32] = "Status: ";
 199         char *s = strchr(stat, '\0');
 200         if (mail->stat & STAT_READ)
 201                 *s++ = 'R';
 202         *s++ = 'O';
 203         *s++ = '\n';
 204         if (!mail->stat_hdr) {
 205                 xwrite(fd, mail->head, mail->body - mail->head);
 206                 xwrite(fd, stat, s - stat);
 207                 xwrite(fd, mail->body, mail->body_len);
 208                 return;
 209         }
 210         if (!mail_changed(mail)) {
 211                 xwrite(fd, mail->head, mail->len);
 212         } else {
 213                 char *hdr_end = strchr(mail->stat_hdr, '\n');
 214                 xwrite(fd, mail->head, mail->stat_hdr - mail->head);
 215                 xwrite(fd, stat, s - stat);
 216                 if (hdr_end)
 217                         xwrite(fd, hdr_end + 1,
 218                                 mail->head + mail->len - hdr_end - 1);
 219         }
 220 }
 221
 222 static int mbox_changed(struct mbox *mbox)
 223 {
 224         int i;
 225         for (i = 0; i < mbox->n; i++)
 226                 if (mail_changed(&mbox->mails[i]))
 227                         return 1;
 228         return 0;
 229 }
 230
 231 int mbox_write(struct mbox *mbox)
 232 {
 233         int fd;
 234         int i = 0;
 235         if (mbox_inc(mbox) == -1)
 236                 return -1;
 237         if (!mbox_changed(mbox))
 238                 return 0;
 239         fd = open(mbox->path, O_WRONLY | O_CREAT, S_IRUSR | S_IWUSR);
 240         while (i < mbox->n) {
 241                 char *beg = mbox->mails[i].head;
 242                 char *end = mbox->mbox + mbox->len;
 243                 while (i < mbox->n && !mail_changed(&mbox->mails[i]))
 244                         i++;
 245                 if (i < mbox->n)
 246                         end = mbox->mails[i].head;
 247                 xwrite(fd, beg, end - beg);
 248                 if (i < mbox->n || !(mbox->mails[i].stat & STAT_DEL))
 249                         mail_write(&mbox->mails[i++], fd);
 250         }
 251         close(fd);
 252         return 0;
 253 }