mailx.c

   1 #include <ctype.h>
   2 #include <stdlib.h>
   3 #include <string.h>
   4 #include <unistd.h>
   5 #include <sys/types.h>
   6 #include <sys/wait.h>
   7 #include "mbox.h"
   8
   9 #define MIN(a, b)               ((a) < (b) ? (a) : (b))
  10 #define BUFSIZE                 (1 << 12)
  11 #define PAGER                   "pgmail"
  12
  13 static char buf[BUFSIZE];
  14 static int cur;
  15 static int len;
  16
  17 static int read_line(char *dst, int size)
  18 {
  19         int nw = 0;
  20         while (1) {
  21                 int cur_len = MIN(len - cur, size - nw - 1);
  22                 char *nl = memchr(buf + cur, '\n', cur_len);
  23                 int nr = nl ? nl - buf - cur + 1 : cur_len;
  24                 if (nr) {
  25                         memcpy(dst + nw, buf + cur, nr);
  26                         nw += nr;
  27                         cur += nr;
  28                         dst[nw] = '\0';
  29                 }
  30                 if (nl || nw == size - 1)
  31                         return nw;
  32                 cur = 0;
  33                 if ((len = read(STDIN_FILENO, buf, BUFSIZE)) <= 0)
  34                         return -1;
  35         }
  36         return nw;
  37 }
  38
  39 static void till_eol(char *s)
  40 {
  41         char *r = s;
  42         while (*s && *s != '\r' && *s != '\n')
  43                 s++;
  44         write(1, r, s - r);
  45         write(1, "\n", 1);
  46 }
  47
  48 static void cmd_page(struct mbox *mbox, char *args)
  49 {
  50         struct mail *mail;
  51         pid_t pid;
  52         int fds[2];
  53         mail = &mbox->mails[0];
  54         pipe(fds);
  55         if (!(pid = fork())) {
  56                 char *args[] = {PAGER, NULL};
  57                 close(fds[1]);
  58                 dup2(fds[0], STDIN_FILENO);
  59                 execvp(PAGER, args);
  60                 exit(1);
  61         }
  62         close(fds[0]);
  63         write(fds[1], mail->head, mail->len);
  64         close(fds[1]);
  65         waitpid(pid, NULL, 0);
  66 }
  67
  68 static char *cut_cmd(char *dst, char *s)
  69 {
  70         while (isalpha(*s)) {
  71                 *dst++ = *s++;
  72         }
  73         *dst = '\0';
  74         return s;
  75 }
  76
  77 static void cmd_head(struct mbox *mbox, char *args)
  78 {
  79         int i;
  80         int n = MIN(mbox->n, 10);
  81         for (i = 0; i < n; i++)
  82                 if (mbox->mails[i].subject)
  83                         till_eol(mbox->mails[i].subject);
  84 }
  85
  86 static void loop(struct mbox *mbox)
  87 {
  88         char line[128];
  89         char cmd[128];
  90         while (read_line(line, sizeof(line)) > 0) {
  91                 char *args = cut_cmd(cmd, line);
  92                 int len = strlen(cmd);
  93                 if (!strncmp("header", cmd, len))
  94                         cmd_head(mbox, args);
  95                 if (!strncmp("page", cmd, len))
  96                         cmd_page(mbox, args);
  97                 if (!strncmp("quit", cmd, len))
  98                         return;
  99                 if (!strncmp("x", cmd, len) || !strncmp("exit", cmd, len))
 100                         return;
 101         }
 102 }
 103
 104 int main(int argc, char *argv[])
 105 {
 106         int i = 0;
 107         struct mbox *mbox;
 108         char *filename = NULL;
 109         while (++i < argc)
 110                 if (!strcmp("-f", argv[i]))
 111                         filename = argv[++i];
 112         if (filename) {
 113                 mbox = mbox_alloc(filename);
 114                 loop(mbox);
 115                 mbox_free(mbox);
 116         }
 117         return 0;
 118 }