|
3 | 3 |
|
4 | 4 | use unix::solarish::*; |
5 | 5 |
|
| 6 | +const PTEM: &[u8] = b"ptem\0"; |
| 7 | +const LDTERM: &[u8] = b"ldterm\0"; |
| 8 | + |
6 | 9 | pub unsafe fn cfmakeraw(termios: *mut ::termios) { |
7 | 10 | (*termios).c_iflag &= !(IMAXBEL |
8 | 11 | | IGNBRK |
@@ -45,3 +48,136 @@ pub unsafe fn cfsetspeed( |
45 | 48 | ::cfsetospeed(termios, speed); |
46 | 49 | 0 |
47 | 50 | } |
| 51 | + |
| 52 | +unsafe fn bail(fdm: ::c_int, fds: ::c_int) -> ::c_int { |
| 53 | + let e = *___errno(); |
| 54 | + if fds >= 0 { |
| 55 | + ::close(fds); |
| 56 | + } |
| 57 | + if fdm >= 0 { |
| 58 | + ::close(fdm); |
| 59 | + } |
| 60 | + *___errno() = e; |
| 61 | + return -1; |
| 62 | +} |
| 63 | + |
| 64 | +pub unsafe fn openpty( |
| 65 | + amain: *mut ::c_int, |
| 66 | + asubord: *mut ::c_int, |
| 67 | + name: *mut ::c_char, |
| 68 | + termp: *const termios, |
| 69 | + winp: *const ::winsize, |
| 70 | +) -> ::c_int { |
| 71 | + // Open the main pseudo-terminal device, making sure not to set it as the |
| 72 | + // controlling terminal for this process: |
| 73 | + let fdm = ::posix_openpt(O_RDWR | O_NOCTTY); |
| 74 | + if fdm < 0 { |
| 75 | + return -1; |
| 76 | + } |
| 77 | + |
| 78 | + // Set permissions and ownership on the subordinate device and unlock it: |
| 79 | + if ::grantpt(fdm) < 0 || ::unlockpt(fdm) < 0 { |
| 80 | + return bail(fdm, -1); |
| 81 | + } |
| 82 | + |
| 83 | + // Get the path name of the subordinate device: |
| 84 | + let subordpath = ::ptsname(fdm); |
| 85 | + if subordpath.is_null() { |
| 86 | + return bail(fdm, -1); |
| 87 | + } |
| 88 | + |
| 89 | + // Open the subordinate device without setting it as the controlling |
| 90 | + // terminal for this process: |
| 91 | + let fds = ::open(subordpath, O_RDWR | O_NOCTTY); |
| 92 | + if fds < 0 { |
| 93 | + return bail(fdm, -1); |
| 94 | + } |
| 95 | + |
| 96 | + // Check if the STREAMS modules are already pushed: |
| 97 | + let setup = ::ioctl(fds, I_FIND, LDTERM.as_ptr()); |
| 98 | + if setup < 0 { |
| 99 | + return bail(fdm, fds); |
| 100 | + } else if setup == 0 { |
| 101 | + // The line discipline is not present, so push the appropriate STREAMS |
| 102 | + // modules for the subordinate device: |
| 103 | + if ::ioctl(fds, I_PUSH, PTEM.as_ptr()) < 0 |
| 104 | + || ::ioctl(fds, I_PUSH, LDTERM.as_ptr()) < 0 |
| 105 | + { |
| 106 | + return bail(fdm, fds); |
| 107 | + } |
| 108 | + } |
| 109 | + |
| 110 | + // If provided, set the terminal parameters: |
| 111 | + if !termp.is_null() && ::tcsetattr(fds, TCSAFLUSH, termp) != 0 { |
| 112 | + return bail(fdm, fds); |
| 113 | + } |
| 114 | + |
| 115 | + // If provided, set the window size: |
| 116 | + if !winp.is_null() && ::ioctl(fds, TIOCSWINSZ, winp) < 0 { |
| 117 | + return bail(fdm, fds); |
| 118 | + } |
| 119 | + |
| 120 | + // If the caller wants the name of the subordinate device, copy it out. |
| 121 | + // |
| 122 | + // Note that this is a terrible interface: there appears to be no standard |
| 123 | + // upper bound on the copy length for this pointer. Nobody should pass |
| 124 | + // anything but NULL here, preferring instead to use ptsname(3C) directly. |
| 125 | + if !name.is_null() { |
| 126 | + ::strcpy(name, subordpath); |
| 127 | + } |
| 128 | + |
| 129 | + *amain = fdm; |
| 130 | + *asubord = fds; |
| 131 | + 0 |
| 132 | +} |
| 133 | + |
| 134 | +pub unsafe fn forkpty( |
| 135 | + amain: *mut ::c_int, |
| 136 | + name: *mut ::c_char, |
| 137 | + termp: *const termios, |
| 138 | + winp: *const ::winsize, |
| 139 | +) -> ::pid_t { |
| 140 | + let mut fds = -1; |
| 141 | + |
| 142 | + if openpty(amain, &mut fds, name, termp, winp) != 0 { |
| 143 | + return -1; |
| 144 | + } |
| 145 | + |
| 146 | + let pid = ::fork(); |
| 147 | + if pid < 0 { |
| 148 | + return bail(*amain, fds); |
| 149 | + } else if pid > 0 { |
| 150 | + // In the parent process, we close the subordinate device and return the |
| 151 | + // process ID of the new child: |
| 152 | + ::close(fds); |
| 153 | + return pid; |
| 154 | + } |
| 155 | + |
| 156 | + // The rest of this function executes in the child process. |
| 157 | + |
| 158 | + // Close the main side of the pseudo-terminal pair: |
| 159 | + ::close(*amain); |
| 160 | + |
| 161 | + // Use TIOCSCTTY to set the subordinate device as our controlling |
| 162 | + // terminal. This will fail (with ENOTTY) if we are not the leader in |
| 163 | + // our own session, so we call setsid() first. Finally, arrange for |
| 164 | + // the pseudo-terminal to occupy the standard I/O descriptors. |
| 165 | + if ::setsid() < 0 |
| 166 | + || ::ioctl(fds, TIOCSCTTY, 0) < 0 |
| 167 | + || ::dup2(fds, 0) < 0 |
| 168 | + || ::dup2(fds, 1) < 0 |
| 169 | + || ::dup2(fds, 2) < 0 |
| 170 | + { |
| 171 | + // At this stage there are no particularly good ways to handle failure. |
| 172 | + // Exit as abruptly as possible, using _exit() to avoid messing with any |
| 173 | + // state still shared with the parent process. |
| 174 | + ::_exit(EXIT_FAILURE); |
| 175 | + } |
| 176 | + // Close the inherited descriptor, taking care to avoid closing the standard |
| 177 | + // descriptors by mistake: |
| 178 | + if fds > 2 { |
| 179 | + ::close(fds); |
| 180 | + } |
| 181 | + |
| 182 | + 0 |
| 183 | +} |
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