[hackers] [st] use stdio(3) || Matthias-Christian Ott

changeset: 42:78572611076a
tag: tip
user: Matthias-Christian Ott <ott_AT_enolink.de>
date: Mon Aug 25 17:56:00 2008 +0200
files: std.c
description:
use stdio(3)

diff -r 5b93836536fd -r 78572611076a std.c
--- a/std.c Mon Aug 25 16:29:37 2008 +0200
+++ b/std.c Mon Aug 25 17:56:00 2008 +0200
@@ -15,6 +15,7 @@
 #include <sys/wait.h>
 #include <ctype.h>
 #include <err.h>
+#include <errno.h>
 #include <fcntl.h>
 #if !(_POSIX_C_SOURCE >= 200112L || _XOPEN_SOURCE >= 600)
 #include <pty.h>
@@ -36,15 +37,8 @@
         int n;
 } RingBuffer;
 
-typedef struct {
- unsigned char data[BUFSIZ];
- int i, n;
- int fd;
-} ReadBuffer;
-
 static void buffer(char c);
 static void cmd(const char *cmdstr, ...);
-static int getch(ReadBuffer *buf);
 static void getpty(void);
 static void movea(int x, int y);
 static void mover(int x, int y);
@@ -54,7 +48,6 @@
 static void shell(void);
 static void sigchld(int n);
 static char unbuffer(void);
-static void ungetch(ReadBuffer *buf, int c);
 
 static int cols = 80, lines = 25;
 static int cx = 0, cy = 0;
@@ -63,7 +56,7 @@
 static _Bool bold, digit, qmark;
 static pid_t pid;
 static RingBuffer buf;
-static ReadBuffer cmdbuf, ptmbuf;
+static FILE *fptm;
 
 void
 buffer(char c) {
@@ -84,17 +77,6 @@
         va_start(ap, cmdstr);
         vfprintf(stdout, cmdstr, ap);
         va_end(ap);
-}
-
-int
-getch(ReadBuffer *buf) {
- if(buf->i++ >= buf->n) {
- buf->n = read(buf->fd, buf->data, BUFSIZ);
- if(buf->n == -1)
- err(EXIT_FAILURE, "cannot read");
- buf->i = 0;
- }
- return buf->data[buf->i];
 }
 
 void
@@ -121,10 +103,10 @@
         int arg[16];
 
         memset(arg, 0, LENGTH(arg));
- c = getch(&ptmbuf);
+ c = getc(fptm);
         switch(c) {
         case '[':
- c = getch(&ptmbuf);
+ c = getc(fptm);
                 for(j = 0; j < LENGTH(arg);) {
                         if(isdigit(c)) {
                                 digit = 1;
@@ -146,7 +128,7 @@
                                 }
                                 break;
                         }
- c = getch(&ptmbuf);
+ c = getc(fptm);
                 }
                 switch(c) {
                 case '@':
@@ -220,7 +202,7 @@
                 break;
         default:
                 putchar('\033');
- ungetch(&ptmbuf, c);
+ ungetc(c, fptm);
         }
 }
 
@@ -308,13 +290,6 @@
         return c;
 }
 
-void
-ungetch(ReadBuffer *buf, int c) {
- if(buf->i + 1 >= buf->n)
- errx(EXIT_FAILURE, "buffer full");
- buf->data[buf->i++] = c;
-}
-
 int
 main(int argc, char *argv[]) {
         fd_set rfds;
@@ -325,28 +300,31 @@
                 errx(EXIT_FAILURE, "usage: std [-v]");
         getpty();
         shell();
- cmdbuf.fd = STDIN_FILENO;
- ptmbuf.fd = ptm;
         FD_ZERO(&rfds);
         FD_SET(STDIN_FILENO, &rfds);
         FD_SET(ptm, &rfds);
+ if(!(fptm = fdopen(ptm, "r+")))
+ err(EXIT_FAILURE, "cannot open pty");
+ if(fcntl(ptm, F_SETFL, O_NONBLOCK) == -1)
+ err(EXIT_FAILURE, "cannot set pty to non-blocking mode");
+ if(fcntl(STDIN_FILENO, F_SETFL, O_NONBLOCK) == -1)
+ err(EXIT_FAILURE, "cannot set stdin to non-blocking mode");
         for(;;) {
- if(select(ptm + 1, &rfds, NULL, NULL, NULL) == -1)
+ if(select(MAX(ptm, STDIN_FILENO) + 1, &rfds, NULL, NULL, NULL) == -1)
                         err(EXIT_FAILURE, "cannot select");
- if(FD_ISSET(STDIN_FILENO, &rfds))
- do {
- c = getch(&cmdbuf);
- switch(c) {
- case ':':
- parsecmd();
- break;
- default:
+ if(FD_ISSET(ptm, &rfds)) {
+ for(;;) {
+ if((c = getc(fptm)) == EOF) {
+ if(feof(fptm)) {
+ FD_CLR(ptm, &rfds);
+ fflush(fptm);
+ break;
+ }
+ if(errno != EAGAIN)
+ err(EXIT_FAILURE, "cannot read from pty");
+ fflush(stdout);
                                         break;
                                 }
- } while(cmdbuf.i < cmdbuf.n);
- if(FD_ISSET(ptm, &rfds)) {
- do {
- c = getch(&ptmbuf);
                                 switch(c) {
                                 case '\033':
                                         parseesc();
@@ -354,8 +332,31 @@
                                 default:
                                         putchar(c);
                                 }
- } while(ptmbuf.i < ptmbuf.n);
+ }
                         fflush(stdout);
+ }
+ if(FD_ISSET(STDIN_FILENO, &rfds)) {
+ for(;;) {
+ if((c = getchar()) == EOF) {
+ if(feof(stdin)) {
+ FD_CLR(STDIN_FILENO, &rfds);
+ fflush(fptm);
+ break;
+ }
+ if(errno != EAGAIN)
+ err(EXIT_FAILURE, "cannot read from stdin");
+ fflush(fptm);
+ break;
+ }
+ switch(c) {
+ case ':':
+ parsecmd();
+ break;
+ default:
+ putc(c, fptm);
+ }
+ }
+ fflush(fptm);
                 }
         }
         return 0;
Received on Mon Aug 25 2008 - 15:56:25 UTC