pty/pty_master_open.c

+/* pty_master_open.c
+
+   Implement our ptyMasterOpen() function, based on UNIX 98 pseudoterminals.
+   See comments below.
+
+   See also pty_master_open_bsd.c.
+*/
+#if ! defined(__sun)
+        /* Prevents ptsname() declaration being visible on Solaris 8 */
+#if ! defined(_XOPEN_SOURCE) || _XOPEN_SOURCE < 600
 #define _XOPEN_SOURCE 600
+#endif
+#endif
 #include <stdlib.h>
 #include <fcntl.h>
 #include "pty_master_open.h"            /* Declares ptyMasterOpen() */
 #include "tlpi_hdr.h"
 
+/* Some implementations don't have posix_openpt() */
+
+#if defined(__sun)                      /* Not on Solaris 8 */
+#define NO_POSIX_OPENPT
+#endif
+
+#ifdef NO_POSIX_OPENPT
+
+static int
+posix_openpt(int flags)
+{
+    return open("/dev/ptmx", flags);
+}
+
+#endif
+
+/* Open a pty master, returning file descriptor, or -1 on error.
+   On successful completion, the name of the corresponding pty
+   slave is returned in 'slaveName'. 'snLen' should be set to
+   indicate the size of the buffer pointed to by 'slaveName'. */
+
 int
 ptyMasterOpen(char *slaveName, size_t snLen)
 {
     int masterFd, savedErrno;
     char *p;
 
     masterFd = posix_openpt(O_RDWR | O_NOCTTY);         /* Open pty master */
     if (masterFd == -1)
         return -1;
 
     if (grantpt(masterFd) == -1) {              /* Grant access to slave pty */
         savedErrno = errno;
         close(masterFd);                        /* Might change 'errno' */
         errno = savedErrno;
         return -1;
     }
 
     if (unlockpt(masterFd) == -1) {             /* Unlock slave pty */
         savedErrno = errno;
         close(masterFd);                        /* Might change 'errno' */
         errno = savedErrno;
         return -1;
     }
 
     p = ptsname(masterFd);                      /* Get slave pty name */
     if (p == NULL) {
         savedErrno = errno;
         close(masterFd);                        /* Might change 'errno' */
         errno = savedErrno;
         return -1;
     }
 
     if (strlen(p) < snLen) {
         strncpy(slaveName, p, snLen);
     } else {                    /* Return an error if buffer too small */
         close(masterFd);
         errno = EOVERFLOW;
         return -1;
     }
 
     return masterFd;
 }