mbox.c

   1 #include <ctype.h>
   2 #include <errno.h>
   3 #include <fcntl.h>
   4 #include <stdlib.h>
   5 #include <string.h>
   6 #include <time.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 "str.h"
  13 #include "util.h"
  14
  15 #define INCSIZE         (1 << 22)
  16
  17 static void set_atime(char *filename)
  18 {
  19         struct stat st;
  20         struct utimbuf times;
  21         stat(filename, &st);
  22         times.actime = time(NULL);
  23         times.modtime = st.st_mtime;
  24         utime(filename, &times);
  25 }
  26
  27 static char *mail_start(char *r, char *e)
  28 {
  29         char *s = r;
  30         char *t;
  31         while (s < e) {
  32                 if (!strncmp("From ", s, 5) && (s == r || *(s - 1) == '\n'))
  33                         break;
  34                 t = memchr(s + 1, 'F', e - s - 1);
  35                 s = t ? t : e;
  36         }
  37         return s;
  38 }
  39
  40 static char *mail_hdrs(struct mail *mail, char *s)
  41 {
  42         static char stat[] = "Status:";
  43         char *r;
  44         while (s && *s && *s != '\r' && *s != '\n') {
  45                 if (isalpha(*s) && mail->nhdrs < MAXHDRS)
  46                         mail->hdrs[mail->nhdrs++] = s;
  47                 if (!strncmp(stat, s, sizeof(stat) - 1))
  48                         mail->stat_hdr = s;
  49                 if ((r = strchr(s + 1, '\n')))
  50                         s = r + 1;
  51                 else
  52                         s = strchr(s + 1, '\0');
  53         }
  54         mail->hdrs[mail->nhdrs] = s;
  55         return s;
  56 }
  57
  58 char *mail_hdr(struct mail *mail, char *hdr)
  59 {
  60         int i;
  61         for (i = 1; i < mail->nhdrs; i++)
  62                 if (startswith(mail->hdrs[i], hdr))
  63                         return mail->hdrs[i];
  64         return NULL;
  65 }
  66
  67 int hdr_len(char *hdr)
  68 {
  69         char *s = hdr;
  70         while (*s) {
  71                 char *r = strchr(s, '\n');
  72                 if (!r)
  73                         return strchr(s, '\0') - hdr;
  74                 s = r + 1;
  75                 if (!isspace(*s))
  76                         return s - hdr;
  77         }
  78         return 0;
  79 }
  80
  81 static void mail_stat(struct mail *mail)
  82 {
  83         if (mail->stat_hdr) {
  84                 char *s = mail->stat_hdr + strlen("Status:");
  85                 while (*s && *s != '\r' && *s != '\n') {
  86                         switch (*s++) {
  87                         case 'O':
  88                                 mail->stat |= STAT_OLD;
  89                                 break;
  90                         case 'N':
  91                                 mail->stat |= STAT_NEW;
  92                                 break;
  93                         case 'R':
  94                                 mail->stat |= STAT_READ;
  95                                 break;
  96                         }
  97                 }
  98                 mail->orig_stat = mail->stat;
  99         } else {
 100                 mail->stat = STAT_NEW;
 101         }
 102 }
 103
 104 char *mail_read(struct mail *mail, char *s, char *e)
 105 {
 106         char *end;
 107         mail->head = s;
 108         mail->body = mail_hdrs(mail, s);
 109         end = mail_start(mail->body, e);
 110         mail->len = end - mail->head;
 111         mail->body_len = end - mail->body;
 112         mail_stat(mail);
 113         return end;
 114 }
 115
 116 static int read_mails(struct mbox *mbox, char *s, char *e)
 117 {
 118         while (s && *s && mbox->n < MAXMAILS)
 119                 s = mail_read(&mbox->mails[mbox->n++], s, e);
 120         return mbox->n == MAXMAILS;
 121 }
 122
 123 int mbox_inc(struct mbox *mbox)
 124 {
 125         int fd = open(mbox->path, O_RDONLY);
 126         int old_n = mbox->n;
 127         int old_len = mbox->len;
 128         int len = file_size(fd);
 129         if (fd == -1)
 130                 return 0;
 131         if (!mbox->mbox) {
 132                 mbox->size = len + INCSIZE + 1;
 133                 mbox->mbox = malloc(mbox->size);
 134         }
 135         if (len > mbox->size - 1)
 136                 return -1;
 137         if (mbox->len)
 138                 lseek(fd, mbox->len, SEEK_SET);
 139         mbox->len += xread(fd, mbox->mbox + mbox->len, len);
 140         mbox->mbox[mbox->len] = '\0';
 141         close(fd);
 142         set_atime(mbox->path);
 143         if (old_len < mbox->len)
 144                 if (read_mails(mbox, mbox->mbox + old_len,
 145                                 mbox->mbox + mbox->len))
 146                         return -1;
 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         if (mbox_inc(mbox) < 0) {
 157                 mbox_free(mbox);
 158                 return NULL;
 159         }
 160         return mbox;
 161 }
 162
 163 void mbox_free(struct mbox *mbox)
 164 {
 165         free(mbox->mbox);
 166         free(mbox);
 167 }
 168
 169 int mail_head(struct mail *mail, char *buf, int buf_len,
 170                 char **hdrs, int n)
 171 {
 172         int i, j;
 173         char *s = buf;
 174         char *dead = s + buf_len;
 175         for (i = 0; i < n; i++) {
 176                 char *pat = hdrs[i];
 177                 for (j = 0; j < mail->nhdrs; j++) {
 178                         char *hdr = mail->hdrs[j];
 179                         if (startswith(hdr, pat)) {
 180                                 int hdr_len = mail->hdrs[j + 1] - hdr;
 181                                 if (s + hdr_len > dead)
 182                                         hdr_len = dead - s;
 183                                 memcpy(s, hdr, hdr_len);
 184                                 s += hdr_len;
 185                                 break;
 186                         }
 187                 }
 188         }
 189         *s = '\0';
 190         return s - buf;
 191 }
 192
 193 static int mail_changed(struct mail *mail)
 194 {
 195         return mail->orig_stat != mail->stat;
 196 }
 197
 198 void mail_write(struct mail *mail, int fd)
 199 {
 200         char stat[32] = "Status: ";
 201         char *s = strchr(stat, '\0');
 202         if (mail->stat & STAT_READ)
 203                 *s++ = 'R';
 204         if (mail->stat & (STAT_OLD | STAT_READ))
 205                 *s++ = 'O';
 206         if (mail->stat & STAT_NEW)
 207                 *s++ = 'N';
 208         *s++ = '\n';
 209         if (!mail_changed(mail)) {
 210                 xwrite(fd, mail->head, mail->len);
 211         } else {
 212                 char *hdr_beg = mail->body;
 213                 char *hdr_end = mail->body;
 214                 if (mail->stat_hdr) {
 215                         char *nl = strchr(mail->stat_hdr, '\n');
 216                         hdr_beg = mail->stat_hdr;
 217                         hdr_end = nl ? nl + 1 : mail->body;
 218                 }
 219                 xwrite(fd, mail->head, hdr_beg - mail->head);
 220                 xwrite(fd, stat, s - stat);
 221                 if (hdr_end)
 222                         xwrite(fd, hdr_end, mail->head + mail->len - hdr_end);
 223         }
 224 }
 225
 226 static int mbox_changed(struct mbox *mbox)
 227 {
 228         int i;
 229         for (i = 0; i < mbox->n; i++)
 230                 if (mail_changed(&mbox->mails[i]))
 231                         return 1;
 232         return 0;
 233 }
 234
 235 int mbox_write(struct mbox *mbox)
 236 {
 237         int fd;
 238         int i = 0;
 239         if (mbox_inc(mbox) < 0)
 240                 return -1;
 241         if (!mbox_changed(mbox))
 242                 return 0;
 243         fd = open(mbox->path, O_WRONLY | O_TRUNC | O_CREAT, S_IRUSR | S_IWUSR);
 244         while (i < mbox->n) {
 245                 char *beg = mbox->mails[i].head;
 246                 char *end = mbox->mbox + mbox->len;
 247                 while (i < mbox->n && !mail_changed(&mbox->mails[i]))
 248                         i++;
 249                 if (i < mbox->n)
 250                         end = mbox->mails[i].head;
 251                 xwrite(fd, beg, end - beg);
 252                 if (i < mbox->n && !(mbox->mails[i].stat & STAT_DEL))
 253                         mail_write(&mbox->mails[i], fd);
 254                 i++;
 255         }
 256         close(fd);
 257         return 0;
 258 }