Create ish_open.c

ISHELL-v0.3/ish_open.c

@@ -0,0 +1,66 @@
+/* ISHELL: command execution functions
+ * by: Peter Kieltyka (elux)
+ * http://peter.eluks.com / [email protected]
+ * Note: The functions below are derived from code bighawk
+ * previously wrote as a substitute for popen(). */
+#include "ishell.h"
+#ifndef OPEN_MAX
+#define OPEN_MAX 1024
+#endif
+
+static  pid_t *childpid = NULL;
+
+int popen2(const char *commandstring) {
+    int i, fds[2];
+    pid_t pid;
+
+    if(childpid == NULL)
+        if((childpid = calloc(OPEN_MAX, sizeof(pid_t))) == NULL)
+            return -1;
+
+    if(socketpair(AF_UNIX, SOCK_STREAM, 0, fds) == -1)
+        return -1;
+
+    if((pid = fork()) < 0)
+        return -1;
+    else if(pid == 0) {
+        close(fds[1]);
+        if(fds[0] != STDIN_FILENO) {
+            dup2(fds[0], STDIN_FILENO);
+            close(fds[0]);
+        }
+        dup2(STDIN_FILENO, STDOUT_FILENO);
+        dup2(STDOUT_FILENO, STDERR_FILENO);
+
+        for(i = 0; i < OPEN_MAX; i++) {
+            if(childpid[i] > 0)
+            close(i);
+        }
+        execl("/bin/sh", "sh", "-c", commandstring, NULL);
+        _exit(127);
+    }
+
+    close(fds[0]);
+    childpid[fds[1]] = pid;
+    return(fds[1]);
+}
+
+int pclose2(int fd) {
+    int stat;
+    pid_t pid;   
+
+    if(childpid == NULL)
+        return -1;
+
+    if(childpid[fd] == 0)
+        return -1;
+
+    close(fd);  
+    pid = childpid[fd];
+
+    while(waitpid(pid, &stat, 0) == -1)
+        if(errno != EINTR)
+            return -1;
+
+    return(stat);
+}