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 <time.h>
   8 #include <unistd.h>
   9 #include <utime.h>
  10 #include <sys/types.h>
  11 #include <sys/stat.h>
  12 #include "mbox.h"
  13 #include "util.h"
  14
  15 #define INCSIZE         (1 << 21)
  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)
  28 {
  29         char *s = r;
  30         char *t;
  31         while (*s) {
  32                 if (!strncmp("From ", s, 5) && (s == r || *(s - 1) == '\n'))
  33                         break;
  34                 if ((t = strchr(s + 1, 'F')))
  35                         s = t;
  36                 else
  37                         s = strchr(s, '\0');
  38         }
  39         return s;
  40 }
  41
  42 static char *mail_hdrs(struct mail *mail, char *s)
  43 {
  44         static char stat[] = "Status:";
  45         char *r;
  46         while (s && *s && *s != '\r' && *s != '\n') {
  47                 if (isalpha(*s) && mail->nhdrs < MAXHDRS)
  48                         mail->hdrs[mail->nhdrs++] = s;
  49                 if (!strncmp(stat, s, sizeof(stat) - 1))
  50                         mail->stat_hdr = s;
  51                 if ((r = strchr(s + 1, '\n')))
  52                         s = r + 1;
  53                 else
  54                         s = strchr(s + 1, '\0');
  55         }
  56         mail->hdrs[mail->nhdrs] = s;
  57         return s;
  58 }
  59
  60 char *mail_hdr(struct mail *mail, char *hdr)
  61 {
  62         int i;
  63         int len = strlen(hdr);
  64         for (i = 1; i < mail->nhdrs; i++)
  65                 if (!strncasecmp(mail->hdrs[i], hdr, len))
  66                         return mail->hdrs[i];
  67         return NULL;
  68 }
  69
  70 int hdr_len(char *hdr)
  71 {
  72         char *s = hdr;
  73         while (*s) {
  74                 char *r = strchr(s, '\n');
  75                 if (!r)
  76                         return strchr(s, '\0') - hdr;
  77                 s = r;
  78                 if (!isspace(*(s + 1)))
  79                         return s - hdr;
  80                 s++;
  81         }
  82         return 0;
  83 }
  84
  85 static void mail_stat(struct mail *mail)
  86 {
  87         if (mail->stat_hdr) {
  88                 char *s = mail->stat_hdr + strlen("Status:");
  89                 while (*s && *s != '\r' && *s != '\n') {
  90                         switch (*s++) {
  91                         case 'O':
  92                                 mail->stat |= STAT_OLD;
  93                                 break;
  94                         case 'N':
  95                                 mail->stat |= STAT_NEW;
  96                                 break;
  97                         case 'R':
  98                                 mail->stat |= STAT_READ;
  99                                 break;
 100                         }
 101                 }
 102                 mail->orig_stat = mail->stat;
 103         } else {
 104                 mail->stat = STAT_NEW;
 105         }
 106 }
 107
 108 char *mail_read(struct mail *mail, char *s)
 109 {
 110         char *end;
 111         mail->head = s;
 112         mail->body = mail_hdrs(mail, s);
 113         end = mail_start(mail->body);
 114         mail->len = end - mail->head;
 115         mail->body_len = end - mail->body;
 116         mail_stat(mail);
 117         return end;
 118 }
 119
 120 static void read_mails(struct mbox *mbox, char *s)
 121 {
 122         while (s && *s)
 123                 s = mail_read(&mbox->mails[mbox->n++], s);
 124 }
 125
 126 int mbox_inc(struct mbox *mbox)
 127 {
 128         int fd = open(mbox->path, O_RDONLY);
 129         int old_n = mbox->n;
 130         int old_len = mbox->len;
 131         int len = file_size(fd);
 132         if (fd == -1)
 133                 return 0;
 134         if (!mbox->mbox) {
 135                 mbox->size = len + INCSIZE + 1;
 136                 mbox->mbox = malloc(mbox->size);
 137         }
 138         if (len > mbox->size - 1)
 139                 return -1;
 140         if (mbox->len)
 141                 lseek(fd, mbox->len, SEEK_SET);
 142         mbox->len += xread(fd, mbox->mbox + mbox->len, len);
 143         mbox->mbox[mbox->len] = '\0';
 144         close(fd);
 145         set_atime(mbox->path);
 146         if (old_len < mbox->len)
 147                 read_mails(mbox, mbox->mbox + old_len);
 148         return mbox->n - old_n;
 149 }
 150
 151 struct mbox *mbox_alloc(char *filename)
 152 {
 153         struct mbox *mbox;
 154         mbox = malloc(sizeof(*mbox));
 155         memset(mbox, 0, sizeof(*mbox));
 156         strcpy(mbox->path, filename);
 157         mbox_inc(mbox);
 158         return mbox;
 159 }
 160
 161 void mbox_free(struct mbox *mbox)
 162 {
 163         free(mbox->mbox);
 164         free(mbox);
 165 }
 166
 167 int mail_head(struct mail *mail, char *buf, int buf_len,
 168                 char **hdrs, int n)
 169 {
 170         int i, j;
 171         char *s = buf;
 172         char *dead = s + buf_len;
 173         for (i = 0; i < n; i++) {
 174                 char *pat = hdrs[i];
 175                 int pat_len = strlen(hdrs[i]);
 176                 for (j = 0; j < mail->nhdrs; j++) {
 177                         char *hdr = mail->hdrs[j];
 178                         if (!strncasecmp(hdr, pat, pat_len)) {
 179                                 int hdr_len = mail->hdrs[j + 1] - hdr;
 180                                 if (s + hdr_len > dead)
 181                                         hdr_len = dead - s;
 182                                 memcpy(s, hdr, hdr_len);
 183                                 s += hdr_len;
 184                                 break;
 185                         }
 186                 }
 187         }
 188         *s = '\0';
 189         return s - buf;
 190 }
 191
 192 static int mail_changed(struct mail *mail)
 193 {
 194         return mail->orig_stat != mail->stat;
 195 }
 196
 197 void mail_write(struct mail *mail, int fd)
 198 {
 199         char stat[32] = "Status: ";
 200         char *s = strchr(stat, '\0');
 201         if (mail->stat & STAT_READ)
 202                 *s++ = 'R';
 203         *s++ = 'O';
 204         *s++ = '\n';
 205         if (!mail->stat_hdr) {
 206                 xwrite(fd, mail->head, mail->body - mail->head);
 207                 xwrite(fd, stat, s - stat);
 208                 xwrite(fd, mail->body, mail->body_len);
 209                 return;
 210         }
 211         if (!mail_changed(mail)) {
 212                 xwrite(fd, mail->head, mail->len);
 213         } else {
 214                 char *hdr_end = strchr(mail->stat_hdr, '\n');
 215                 xwrite(fd, mail->head, mail->stat_hdr - mail->head);
 216                 xwrite(fd, stat, s - stat);
 217                 if (hdr_end)
 218                         xwrite(fd, hdr_end + 1,
 219                                 mail->head + mail->len - hdr_end - 1);
 220         }
 221 }
 222
 223 static int mbox_changed(struct mbox *mbox)
 224 {
 225         int i;
 226         for (i = 0; i < mbox->n; i++)
 227                 if (mail_changed(&mbox->mails[i]))
 228                         return 1;
 229         return 0;
 230 }
 231
 232 int mbox_write(struct mbox *mbox)
 233 {
 234         int fd;
 235         int i = 0;
 236         if (mbox_inc(mbox) == -1)
 237                 return -1;
 238         if (!mbox_changed(mbox))
 239                 return 0;
 240         fd = open(mbox->path, O_WRONLY | O_CREAT, S_IRUSR | S_IWUSR);
 241         while (i < mbox->n) {
 242                 char *beg = mbox->mails[i].head;
 243                 char *end = mbox->mbox + mbox->len;
 244                 while (i < mbox->n && !mail_changed(&mbox->mails[i]))
 245                         i++;
 246                 if (i < mbox->n)
 247                         end = mbox->mails[i].head;
 248                 xwrite(fd, beg, end - beg);
 249                 if (i < mbox->n || !(mbox->mails[i].stat & STAT_DEL))
 250                         mail_write(&mbox->mails[i++], fd);
 251         }
 252         close(fd);
 253         return 0;
 254 }