JasonWoof Got questions, comments, patches, etc.? Contact Jason Woofenden
add accidentally omitted word
[st.git] / std.c
diff --git a/std.c b/std.c
index a7b2f4a..55da9d6 100644 (file)
--- a/std.c
+++ b/std.c
@@ -1,8 +1,25 @@
-/* See LICENSE file for copyright and license details. */
-#include "util.h"
+/* See LICENSE file for copyright and license details.
+ *
+ * Simple terminal daemon is a terminal emulator. It can be used in
+ * combination with simple terminal to emulate a mostly VT100-compatible
+ * terminal.
+ * 
+ * In this process std works like a filter. It reads data from a
+ * pseudo-terminal and parses the escape sequences and transforms them
+ * into an ed(1)-like language. The resulting data is buffered and
+ * written to stdout.
+ * Parallely it reads data from stdin and parses and executes the
+ * commands. The resulting data is written to the pseudo-terminal.
+ */
 #include <sys/types.h>
 #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>
+#endif
 #include <signal.h>
 #include <stdarg.h>
 #include <stdio.h>
 #define MAX(a,b)       (((a) > (b)) ? (a) : (b))
 #define MIN(a,b)       (((a) < (b)) ? (a) : (b))
 
-void buffer(char c);
-void cmd(const char *cmdstr, ...);
-void getpty(void);
-void movea(int x, int y);
-void mover(int x, int y);
-void parseesc(void);
-void scroll(int l);
-void shell(void);
-void sigchld(int n);
-char unbuffer(void);
-
 typedef struct {
        unsigned char data[BUFSIZ];
        int s, e;
        int n;
 } RingBuffer;
 
-int cols = 80, lines = 25;
-int cx = 0, cy = 0;
-int c;
-FILE *fptm = NULL;
-int ptm, pts;
-_Bool bold, digit, qmark;
-pid_t pid;
-RingBuffer buf;
+static void buffer(char c);
+static void cmd(const char *cmdstr, ...);
+static void getpty(void);
+static void movea(int x, int y);
+static void mover(int x, int y);
+static void parsecmd(void);
+static void parseesc(void);
+static void scroll(int l);
+static void shell(void);
+static void sigchld(int n);
+static char unbuffer(void);
+
+static int cols = 80, lines = 25;
+static int cx = 0, cy = 0;
+static int c;
+static int ptm, pts;
+static _Bool bold, digit, qmark;
+static pid_t pid;
+static RingBuffer buf;
+static FILE *fptm;
 
 void
 buffer(char c) {
@@ -67,7 +85,7 @@ movea(int x, int y) {
        y = MAX(y, lines);
        cx = x;
        cy = y;
-       cmd("s %d,%d", x, y);
+       cmd("seek(%d,%d)", x, y);
 }
 
 void
@@ -76,6 +94,10 @@ mover(int x, int y) {
 }
 
 void
+parsecmd(void) {
+}
+
+void
 parseesc(void) {
        int i, j;
        int arg[16];
@@ -95,7 +117,7 @@ parseesc(void) {
                                qmark = 1;
                        else if(c == ';') {
                                if(!digit)
-                                       eprint("syntax error\n");
+                                       errx(EXIT_FAILURE, "syntax error");
                                digit = 0;
                                j++;
                        }
@@ -168,10 +190,10 @@ parseesc(void) {
                                case 0:
                                case 22:
                                        if(bold)
-                                               cmd("b");
+                                               cmd("bold");
                                case 1:
                                        if(!bold)
-                                               cmd("b");
+                                               cmd("bold");
                                        break;
                                }
                        }
@@ -186,7 +208,39 @@ parseesc(void) {
 
 void
 scroll(int l) {
-       cmd("s %d, %d", cx, cy + l);
+       cmd("seek(%d,%d)", cx, cy + l);
+}
+
+void
+getpty(void) {
+       char *ptsdev;
+
+#if defined(_GNU_SOURCE)
+       ptm = getpt();
+#elif _POSIX_C_SOURCE >= 200112L || _XOPEN_SOURCE >= 600
+       ptm = posix_openpt(O_RDWR);
+#else
+       ptm = open("/dev/ptmx", O_RDWR);
+       if(ptm == -1)
+               if(openpty(&ptm, &pts, NULL, NULL, NULL) == -1)
+                       err(EXIT_FAILURE, "cannot open pty");
+#endif
+#if defined(_XOPEN_SOURCE)
+       if(ptm != -1) {
+               if(grantpt(ptm) == -1)
+                       err(EXIT_FAILURE, "cannot grant access to pty");
+               if(unlockpt(ptm) == -1)
+                       err(EXIT_FAILURE, "cannot unlock pty");
+               ptsdev = ptsname(ptm);
+               if(!ptsdev)
+                       err(EXIT_FAILURE, "slave pty name undefined");
+               pts = open(ptsdev, O_RDWR);
+               if(pts == -1)
+                       err(EXIT_FAILURE, "cannot open slave pty");
+       }
+       else
+               err(EXIT_FAILURE, "cannot open pty");
+#endif
 }
 
 void
@@ -198,7 +252,7 @@ shell(void) {
        pid = fork();
        switch(pid) {
        case -1:
-               eprint("error, cannot fork\n");
+               err(EXIT_FAILURE, "cannot fork");
        case 0:
                setsid();
                dup2(pts, STDIN_FILENO);
@@ -219,7 +273,7 @@ sigchld(int n) {
        int ret;
 
        if(waitpid(pid, &ret, 0) == -1)
-               eprintn("error, waiting for child failed");
+               err(EXIT_FAILURE, "waiting for child failed");
        if(WIFEXITED(ret))
                exit(WEXITSTATUS(ret));
        else
@@ -238,23 +292,71 @@ unbuffer(void) {
 
 int
 main(int argc, char *argv[]) {
+       fd_set rfds;
+
        if(argc == 2 && !strcmp("-v", argv[1]))
-               eprint("std-"VERSION", © 2008 Matthias-Christian Ott\n");
+               errx(EXIT_SUCCESS, "std-"VERSION", © 2008 Matthias-Christian Ott");
        else if(argc == 1)
-               eprint("usage: st [-v]\n");
+               errx(EXIT_FAILURE, "usage: std [-v]");
        getpty();
        shell();
-       fptm = fdopen(ptm, "r+");
-       if(!fptm)
-               eprintn("cannot open slave pty");
+       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(;;) {
-               c = getc(fptm);
-               switch(c) {
-               case '\033':
-                       parseesc();
-                       break;
-               default:
-                       putchar(c);
+               if(select(MAX(ptm, STDIN_FILENO) + 1, &rfds, NULL, NULL, NULL) == -1)
+                       err(EXIT_FAILURE, "cannot select");
+               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;
+                               }
+                               switch(c) {
+                               case '\033':
+                                       parseesc();
+                                       break;
+                               default:
+                                       putchar(c);
+                               }
+                       }
+                       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;