ssh: further improvements

- Remove pwd and kill as they suck in a ton of code
- Add background processes
- Add redirection

diff --git a/Applications/util/ssh.c b/Applications/util/ssh.c
index 049e3ad..6236711 100644 (file)
--- a/Applications/util/ssh.c
+++ b/Applications/util/ssh.c
@@ -17,6 +17,7 @@
 #include <unistd.h>
 #include <fcntl.h>
 #include <ctype.h>
+#include <errno.h>
 
 extern char **environ;      /* Location of Envp from executable Header */
 
@@ -27,6 +28,11 @@ char eline[45];                  /* Line for Search command */
 
 char *cmd;
 char *arg[MAX_ARGS];
+char *inrd;
+char *outrd;
+char *exrd;
+int bg;
+
 int infd;
 
 static void writeo(int i)
@@ -58,12 +64,25 @@ static char argstate;
 
 static char *nextarg(void)
 {
-    char *p = argout;
-
+    char *p;
+    char **t;
+redo:
+    p = argout;
+    t = NULL;
     while(isspace(*argptr))
         argptr++;
     if (*argptr == '\0')
         return NULL;
+    if (memcmp(argptr, "2>", 2) == 0) {
+        t = &exrd;
+        argptr += 2;
+    } else if (*argptr == '<') {
+        t = &inrd;
+        argptr++;
+    } else if (*argptr == '>') {
+        t = &outrd;
+        argptr++;
+    }
     while (*argptr != '\0') {
         if (!argstate) {
             if (isspace(*argptr))
@@ -83,6 +102,11 @@ static char *nextarg(void)
     if (*argptr)
         argptr++;
     *argout++ = 0;
+    /* Redirections etc are pulled out of line */
+    if (t) {
+        *t = p;
+        goto redo;
+    }
     return p;
 }
 
@@ -91,9 +115,29 @@ static char *getarg(char *in)
     argstate = 0;
     argptr = in;
     argout = in;
+    inrd = NULL;
+    outrd = NULL;
+    exrd = NULL;
+    bg = 0;
     return nextarg();
 }
 
+static void openf(const char *p, int tfd, int mode)
+{
+    int fd;
+
+    if (p == NULL)
+        return;
+
+    fd = open(p, mode, 0666);
+    if (fd == -1) {
+        perror(p);
+        exit(1);
+    }
+    dup2(fd, tfd);
+    close(fd);
+}
+
 int main(int argc, char *argval[])
 {
     char  *path, *tp, *sp;     /* Pointers for Path Searching */
@@ -120,22 +164,37 @@ int main(int argc, char *argval[])
     cprompt = (getuid() == 0) ? "ssh# " : "ssh$ ";
 
     for (;;) {
-        for (i = 0; i < MAX_ARGS; i++) arg[i] = NULL;
+        const char **argp = arg;
+        for (i = 0; i < MAX_ARGS; i++)
+            *argp++ = NULL;
+        argp = arg;
         do {
             if (infd == 0)
                 write(1, cprompt, 5);
             if ((i = read(infd, buf, 127)) <= 0) {
                 if (infd == 0)
                     return 0;
-                else
+                else {
+                    close(infd);
                     infd = 0;
+                }
             }
-            buf[i - 1] = '\0';   /* Strip newline from fgets */
+            if (buf[i - 1] == '\n')
+                buf[i - 1] = '\0';   /* Strip newline from read() */
            cmd = getarg(buf);
        } while (cmd == NULL);
 
-       for (i = 0; i < MAX_ARGS; i++)
-               arg[i] = nextarg();
+       for (i = 0; i < MAX_ARGS; i++) {
+           *argp = nextarg();
+           if (*argp == NULL)
+               break;
+            argp++;
+        }
+        argp--;
+        if (i && strcmp(*argp, "&") == 0) {
+            bg = 1;
+            *argp = NULL;
+        }
 
         /* Check for User-Requested Exit back to Login Prompt */
         if (strcmp(cmd, "exit") == 0)
@@ -147,18 +206,6 @@ int main(int argc, char *argval[])
             if (stat)
                 perror("cd");
         }
-
-        else if (strcmp(cmd, "pwd") == 0) {
-           if (getcwd(buf, 128)){
-               char *ptr=&buf[strlen(buf)];
-               *ptr++='\n';
-               *ptr=0;
-               write(1, buf, strlen(buf));
-           }
-            else
-                write(1, "pwd: cannot get current directory\n",34);
-        }
-        
         else if (strcmp(cmd, "sync") == 0) {
             sync();
         }
@@ -180,6 +227,7 @@ int main(int argc, char *argval[])
             }
         }
 
+#ifdef SSH_EXPENSIVE
         /* Check for User request to kill a process */
         else if (strcmp(cmd, "kill") == 0) {
             if (arg[0][0] == '-') {
@@ -199,8 +247,19 @@ int main(int argc, char *argval[])
                     perror("kill");
             }
         }
+        else if (strcmp(cmd, "pwd") == 0) {
+           if (getcwd(buf, 128)){
+               char *ptr=&buf[strlen(buf)];
+               *ptr++='\n';
+               *ptr=0;
+               write(1, buf, strlen(buf));
+           }
+            else
+                write(1, "pwd: cannot get current directory\n",34);
+        }
+#endif
 
-        /* Check for environmen variable assignment */
+        /* Check for environment variable assignment */
         else if ((tp = strchr(cmd, '=')) != NULL) {
          *tp='\0';
          if( *(tp+1) == '\0' ) unsetenv( cmd );
@@ -220,6 +279,12 @@ int main(int argc, char *argval[])
                 if (pid == 0) {             /* Child is in context */
                     signal(SIGINT, SIG_DFL);
                     signal(SIGQUIT, SIG_DFL);
+
+                    openf(inrd, 0, O_RDONLY);
+                    openf(outrd, 1, O_WRONLY|O_CREAT);
+                    /* Must be done last */
+                    openf(exrd, 2, O_WRONLY|O_CREAT);
+
                     /* Path search adapted from Univ of Washington's Minix */
                     path = getenv("PATH");  /* Get base of path string, or NULL */
                     eline[0] = '\0';
@@ -243,9 +308,10 @@ int main(int argc, char *argval[])
                     write(2, cmd, strlen(cmd));
                     write(2, "?\n", 2);      /* Say we can't exec */
                     exit(1);
-                }                                   /* Parent is in context */
-                wait(0);                    /* Parent waits for completion */
-                kill(pid, SIGKILL);         /* then kills child process */
+                }
+                /* Wait for the child */
+                if (!bg)
+                    while(waitpid(pid, NULL, 0) != pid && errno == EINTR);
             }
         }
     }