1 files changed, 230 insertions, 0 deletions
diff --git a/src/popen.c b/src/popen.c
new file mode 100644
index 0000000..8bfd935
--- /dev/null
+++ b/src/popen.c
@@ -0,0 +1,230 @@
+/*
+** Copyright (c) 2010 D. Richard Hipp
+**
+** This program is free software; you can redistribute it and/or
+** modify it under the terms of the Simplified BSD License (also
+** known as the "2-Clause License" or "FreeBSD License".)
+
+** This program is distributed in the hope that it will be useful,
+** but without any warranty; without even the implied warranty of
+** merchantability or fitness for a particular purpose.
+**
+** Author contact information:
+**   drh@hwaci.com
+**   http://www.hwaci.com/drh/
+**
+*******************************************************************************
+**
+** This file contains an implementation of a bi-directional popen().
+*/
+#include "config.h"
+#include "popen.h"
+
+#ifdef _WIN32
+#include <windows.h>
+#include <fcntl.h>
+/*
+** Print a fatal error and quit.
+*/
+static void win32_fatal_error(const char *zMsg){
+  fossil_fatal("%s", zMsg);
+}
+#else
+#include <signal.h>
+#include <sys/wait.h>
+#endif
+
+/*
+** The following macros are used to cast pointers to integers and
+** integers to pointers.  The way you do this varies from one compiler
+** to the next, so we have developed the following set of #if statements
+** to generate appropriate macros for a wide range of compilers.
+**
+** The correct "ANSI" way to do this is to use the intptr_t type.
+** Unfortunately, that typedef is not available on all compilers, or
+** if it is available, it requires an #include of specific headers
+** that vary from one machine to the next.
+**
+** This code is copied out of SQLite.
+*/
+#if defined(__PTRDIFF_TYPE__)  /* This case should work for GCC */
+# define INT_TO_PTR(X)  ((void*)(__PTRDIFF_TYPE__)(X))
+# define PTR_TO_INT(X)  ((int)(__PTRDIFF_TYPE__)(X))
+#elif !defined(__GNUC__)       /* Works for compilers other than LLVM */
+# define INT_TO_PTR(X)  ((void*)&((char*)0)[X])
+# define PTR_TO_INT(X)  ((int)(((char*)X)-(char*)0))
+#elif defined(HAVE_STDINT_H)   /* Use this case if we have ANSI headers */
+# define INT_TO_PTR(X)  ((void*)(intptr_t)(X))
+# define PTR_TO_INT(X)  ((int)(intptr_t)(X))
+#else                          /* Generates a warning - but it always works */
+# define INT_TO_PTR(X)  ((void*)(X))
+# define PTR_TO_INT(X)  ((int)(X))
+#endif
+
+
+#ifdef _WIN32
+/*
+** On windows, create a child process and specify the stdin, stdout,
+** and stderr channels for that process to use.
+**
+** Return the number of errors.
+*/
+static int win32_create_child_process(
+  wchar_t *zCmd,       /* The command that the child process will run */
+  HANDLE hIn,          /* Standard input */
+  HANDLE hOut,         /* Standard output */
+  HANDLE hErr,         /* Standard error */
+  DWORD *pChildPid     /* OUT: Child process handle */
+){
+  STARTUPINFOW si;
+  PROCESS_INFORMATION pi;
+  BOOL rc;
+
+  memset(&si, 0, sizeof(si));
+  si.cb = sizeof(si);
+  si.dwFlags = STARTF_USESTDHANDLES;
+  SetHandleInformation(hIn, HANDLE_FLAG_INHERIT, TRUE);
+  si.hStdInput  = hIn;
+  SetHandleInformation(hOut, HANDLE_FLAG_INHERIT, TRUE);
+  si.hStdOutput = hOut;
+  SetHandleInformation(hErr, HANDLE_FLAG_INHERIT, TRUE);
+  si.hStdError  = hErr;
+  rc = CreateProcessW(
+     NULL,  /* Application Name */
+     zCmd,  /* Command-line */
+     NULL,  /* Process attributes */
+     NULL,  /* Thread attributes */
+     TRUE,  /* Inherit Handles */
+     0,     /* Create flags  */
+     NULL,  /* Environment */
+     NULL,  /* Current directory */
+     &si,   /* Startup Info */
+     &pi    /* Process Info */
+  );
+  if( rc ){
+    CloseHandle( pi.hProcess );
+    CloseHandle( pi.hThread );
+    *pChildPid = pi.dwProcessId;
+  }else{
+    win32_fatal_error("cannot create child process");
+  }
+  return rc!=0;
+}
+#endif
+
+/*
+** Create a child process running shell command "zCmd".  *ppOut is
+** a FILE that becomes the standard input of the child process.
+** (The caller writes to *ppOut in order to send text to the child.)
+** *ppIn is stdout from the child process.  (The caller
+** reads from *ppIn in order to receive input from the child.)
+** Note that *ppIn is an unbuffered file descriptor, not a FILE.
+** The process ID of the child is written into *pChildPid.
+**
+** Return the number of errors.
+*/
+int popen2(
+  const char *zCmd,      /* Command to run in the child process */
+  int *pfdIn,            /* Read from child using this file descriptor */
+  FILE **ppOut,          /* Write to child using this file descriptor */
+  int *pChildPid,        /* PID of the child process */
+  int bDirect            /* 0: run zCmd as a shell cmd.  1: run directly */
+){
+#ifdef _WIN32
+  HANDLE hStdinRd, hStdinWr, hStdoutRd, hStdoutWr, hStderr;
+  SECURITY_ATTRIBUTES saAttr;
+  DWORD childPid = 0;
+  int fd;
+
+  saAttr.nLength = sizeof(saAttr);
+  saAttr.bInheritHandle = TRUE;
+  saAttr.lpSecurityDescriptor = NULL;
+  hStderr = GetStdHandle(STD_ERROR_HANDLE);
+  if( !CreatePipe(&hStdoutRd, &hStdoutWr, &saAttr, 4096) ){
+    win32_fatal_error("cannot create pipe for stdout");
+  }
+  SetHandleInformation( hStdoutRd, HANDLE_FLAG_INHERIT, FALSE);
+
+  if( !CreatePipe(&hStdinRd, &hStdinWr, &saAttr, 4096) ){
+    win32_fatal_error("cannot create pipe for stdin");
+  }
+  SetHandleInformation( hStdinWr, HANDLE_FLAG_INHERIT, FALSE);
+
+  win32_create_child_process(fossil_utf8_to_unicode(zCmd),
+                             hStdinRd, hStdoutWr, hStderr,&childPid);
+  *pChildPid = childPid;
+  *pfdIn = _open_osfhandle(PTR_TO_INT(hStdoutRd), 0);
+  fd = _open_osfhandle(PTR_TO_INT(hStdinWr), 0);
+  *ppOut = _fdopen(fd, "w");
+  CloseHandle(hStdinRd);
+  CloseHandle(hStdoutWr);
+  return 0;
+#else
+  int pin[2], pout[2];
+  *pfdIn = 0;
+  *ppOut = 0;
+  *pChildPid = 0;
+
+  if( pipe(pin)<0 ){
+    return 1;
+  }
+  if( pipe(pout)<0 ){
+    close(pin[0]);
+    close(pin[1]);
+    return 1;
+  }
+  *pChildPid = fork();
+  if( *pChildPid<0 ){
+    close(pin[0]);
+    close(pin[1]);
+    close(pout[0]);
+    close(pout[1]);
+    *pChildPid = 0;
+    return 1;
+  }
+  signal(SIGPIPE,SIG_IGN);
+  if( *pChildPid==0 ){
+    int fd;
+    /* This is the child process */
+    close(0);
+    fd = dup(pout[0]);
+    if( fd!=0 ) fossil_panic("popen() failed to open file descriptor 0");
+    close(pout[0]);
+    close(pout[1]);
+    close(1);
+    fd = dup(pin[1]);
+    if( fd!=1 ) fossil_panic("popen() failed to open file descriptor 1");
+    close(pin[0]);
+    close(pin[1]);
+    if( bDirect ){
+      execl(zCmd, zCmd, (char*)0);
+    }else{
+      execl("/bin/sh", "/bin/sh", "-c", zCmd, (char*)0);
+    }
+    return 1;
+  }else{
+    /* This is the parent process */
+    close(pin[1]);
+    *pfdIn = pin[0];
+    close(pout[0]);
+    *ppOut = fdopen(pout[1], "w");
+    return 0;
+  }
+#endif
+}
+
+/*
+** Close the connection to a child process previously created using
+** popen2().
+*/
+void pclose2(int fdIn, FILE *pOut, int childPid){
+#ifdef _WIN32
+  /* Not implemented, yet */
+  close(fdIn);
+  fclose(pOut);
+#else
+  close(fdIn);
+  fclose(pOut);
+  while( waitpid(0, 0, WNOHANG)>0 ) {}
+#endif
+}