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 ARRAY_SIZE(a)           (sizeof(a) / sizeof((a)[0]))
  10 #define MIN(a, b)               ((a) < (b) ? (a) : (b))
  11 #define MAXLINE                 (1 << 7)
  12 #define BUFSIZE                 (1 << 12)
  13 #define PAGER                   "pgmail"
  14 #define NHEAD                   (1 << 4)
  15
  16 static char *hdr_filt[] = {
  17         "Subject:", "From:", "To:", "Cc:", "Date:", "User-Agent:",
  18         "X-Mailer", "Organization"};
  19
  20 static char buf[BUFSIZE];
  21 static int cur;
  22 static int len;
  23
  24 static int read_line(char *dst, int size)
  25 {
  26         int nw = 0;
  27         while (1) {
  28                 int cur_len = MIN(len - cur, size - nw - 1);
  29                 char *nl = memchr(buf + cur, '\n', cur_len);
  30                 int nr = nl ? nl - buf - cur + 1 : cur_len;
  31                 if (nr) {
  32                         memcpy(dst + nw, buf + cur, nr);
  33                         nw += nr;
  34                         cur += nr;
  35                         dst[nw] = '\0';
  36                 }
  37                 if (nl || nw == size - 1)
  38                         return nw;
  39                 cur = 0;
  40                 if ((len = read(STDIN_FILENO, buf, BUFSIZE)) <= 0)
  41                         return -1;
  42         }
  43         return nw;
  44 }
  45
  46 static void till_eol(char *s)
  47 {
  48         char *r = s;
  49         while (*s && *s != '\r' && *s != '\n')
  50                 s++;
  51         write(1, r, s - r);
  52         write(1, "\n", 1);
  53 }
  54
  55 static char *cut_int(char *dst, char *s)
  56 {
  57         while (isspace(*s))
  58                 s++;
  59         while (isdigit(*s))
  60                 *dst++ = *s++;
  61         *dst = '\0';
  62         return s;
  63 }
  64
  65 static void cmd_page(struct mbox *mbox, char *args)
  66 {
  67         struct mail *mail;
  68         pid_t pid;
  69         int fds[2];
  70         char head[BUFSIZE];
  71         char num[MAXLINE];
  72         int hdr_len;
  73         int n = mbox->c;
  74         args = cut_int(num, args);
  75         if (isdigit(*num))
  76                 n = atoi(num);
  77         if (n < 0 && n >= mbox->n)
  78                 return;
  79         mail = &mbox->mails[n];
  80         mbox->c = n;
  81         pipe(fds);
  82         if (!(pid = fork())) {
  83                 char *args[] = {PAGER, NULL};
  84                 close(fds[1]);
  85                 dup2(fds[0], STDIN_FILENO);
  86                 execvp(PAGER, args);
  87                 exit(1);
  88         }
  89         close(fds[0]);
  90         hdr_len = mail_head(mail, head, sizeof(head),
  91                                 hdr_filt, ARRAY_SIZE(hdr_filt));
  92         write(fds[1], head, hdr_len);
  93         write(fds[1], mail->body, mail->body_len);
  94         close(fds[1]);
  95         waitpid(pid, NULL, 0);
  96 }
  97
  98 static char *cut_cmd(char *dst, char *s)
  99 {
 100         while (isalpha(*s)) {
 101                 *dst++ = *s++;
 102         }
 103         *dst = '\0';
 104         return s;
 105 }
 106
 107 static char *put_int(char *s, int n, int w)
 108 {
 109         int i;
 110         for (i = 0; i < w; i++) {
 111                 s[w - i - 1] = n || !i ? '0' + n % 10 : ' ';
 112                 n = n / 10;
 113         }
 114         return s + w;
 115 }
 116
 117 static void cmd_head(struct mbox *mbox, char *args)
 118 {
 119         int i;
 120         int beg = mbox->c / NHEAD * NHEAD;
 121         int end = MIN(beg + NHEAD, mbox->n);
 122         if (!mbox->n)
 123                 return;
 124         for (i = beg; i < end; i++) {
 125                 char fmt[16] = {0};
 126                 char *s = fmt;
 127                 *s++ = i == mbox->c ? '>' : ' ';
 128                 s = put_int(s, i, 5);
 129                 *s++ = ' ';
 130                 *s++ = ' ';
 131                 write(STDOUT_FILENO, fmt, strlen(fmt));
 132                 if (mbox->mails[i].subject)
 133                         till_eol(mbox->mails[i].subject + 9);
 134         }
 135 }
 136
 137 static void prompt(void)
 138 {
 139         write(STDOUT_FILENO, "? ", 2);
 140 }
 141
 142 static void print(char *s)
 143 {
 144         write(STDOUT_FILENO, s, strlen(s));
 145 }
 146
 147 static void loop(struct mbox *mbox)
 148 {
 149         char line[MAXLINE];
 150         char cmd[MAXLINE];
 151         prompt();
 152         while (read_line(line, sizeof(line)) > 0) {
 153                 char *args = cut_cmd(cmd, line);
 154                 int len = strlen(cmd);
 155                 if (!len) {
 156                         if (mbox->c < mbox->n + 1) {
 157                                 mbox->c++;
 158                                 cmd_page(mbox, args);
 159                         } else {
 160                                 print("EOF\n");
 161                         }
 162                         prompt();
 163                         continue;
 164                 }
 165                 if (!strncmp("page", cmd, len))
 166                         cmd_page(mbox, args);
 167                 if (!strncmp("header", cmd, len))
 168                         cmd_head(mbox, args);
 169                 if (!strncmp("quit", cmd, len))
 170                         return;
 171                 if (!strncmp("x", cmd, len) || !strncmp("exit", cmd, len))
 172                         return;
 173                 prompt();
 174         }
 175 }
 176
 177 int main(int argc, char *argv[])
 178 {
 179         int i = 0;
 180         struct mbox *mbox;
 181         char *filename = NULL;
 182         while (++i < argc)
 183                 if (!strcmp("-f", argv[i]))
 184                         filename = argv[++i];
 185         if (filename) {
 186                 mbox = mbox_alloc(filename);
 187                 loop(mbox);
 188                 mbox_free(mbox);
 189         }
 190         return 0;
 191 }