Initial supprort for creating symlinks in the git layout.

[SVN r84524]

src/engine/builtins.c

@@ -29,6 +29,10 @@
 
 #include <ctype.h>
 
+#ifdef OS_NT
+#include <windows.h>
+#endif
+
 #if defined(USE_EXECUNIX)
 # include <sys/types.h>
 # include <sys/wait.h>
@@ -425,6 +429,11 @@ void load_builtins()
         char const * args [] = { "path", 0 };
         bind_builtin( "MAKEDIR", builtin_makedir, 0, args );
     }
+    
+    {
+        const char * args [] = { "path", 0 };
+        bind_builtin( "READLINK", builtin_readlink, 0, args );
+    }
 
     /* Initialize builtin modules. */
     init_set();
@@ -1827,6 +1836,94 @@ LIST * builtin_makedir( FRAME * frame, int flags )
         : list_new( object_copy( list_front( path ) ) );
 }
 
+LIST *builtin_readlink( FRAME * frame, int flags )
+{
+    const char * path = object_str( list_front( lol_get( frame->args, 0 ) ) );
+#ifdef OS_NT
+
+    /* This struct is declared in ntifs.h which is
+     * part of the Windows Driver Kit.
+     */
+    typedef struct _REPARSE_DATA_BUFFER {
+        ULONG ReparseTag;
+        USHORT ReparseDataLength;
+        USHORT Reserved;
+        union {
+            struct {
+                USHORT SubstituteNameOffset;
+                USHORT SubstituteNameLength;
+                USHORT PrintNameOffset;
+                USHORT PrintNameLength;
+                ULONG Flags;
+                WCHAR PathBuffer[ 1 ];
+            } SymbolicLinkReparseBuffer;
+            struct {
+                USHORT SubstituteNameOffset;
+                USHORT SubstituteNameLength;
+                USHORT PrintNameOffset;
+                USHORT PrintNameLength;
+                WCHAR PathBuffer[ 1 ];
+            } MountPointReparseBuffer;
+            struct {
+                UCHAR DataBuffer[ 1 ];
+            } GenericReparseBuffer;
+        };
+    } REPARSE_DATA_BUFFER;
+
+    HANDLE hLink = CreateFileA( path, 0, FILE_SHARE_READ, NULL, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS | FILE_FLAG_OPEN_REPARSE_POINT, NULL );
+    DWORD n;
+    union {
+        REPARSE_DATA_BUFFER reparse;
+        char data[MAXIMUM_REPARSE_DATA_BUFFER_SIZE];
+    } buf;
+    int okay = DeviceIoControl(hLink, FSCTL_GET_REPARSE_POINT, NULL, 0, &buf, sizeof(buf), &n, NULL);
+
+    CloseHandle( hLink );
+
+    if (okay && buf.reparse.ReparseTag == IO_REPARSE_TAG_SYMLINK )
+    {
+        int index = buf.reparse.SymbolicLinkReparseBuffer.SubstituteNameOffset / 2;
+        int length = buf.reparse.SymbolicLinkReparseBuffer.SubstituteNameLength / 2;
+        char cbuf[MAX_PATH + 1];
+        int numchars = WideCharToMultiByte( CP_ACP, 0, buf.reparse.SymbolicLinkReparseBuffer.PathBuffer + index, length, cbuf, sizeof(cbuf), NULL, NULL );
+        if( numchars >= sizeof(cbuf) )
+        {
+            return 0;
+        }
+        cbuf[numchars] = '\0';
+        return list_new( object_new( cbuf ) );
+    }
+    return 0;
+#else
+    char static_buf[256];
+    char * buf = static_buf;
+    size_t bufsize = 256;
+    LIST * result = 0;
+    while (1) {
+        ssize_t len = readlink( path, buf, bufsize );
+        if ( len < 0 )
+        {
+            break;
+        }
+        else if ( len < bufsize )
+        {
+            buf[ len ] = '\0';
+            result = list_new( object_new( buf ) );
+            break;
+        }
+        if ( buf != static_buf )
+            BJAM_FREE( buf );
+        bufsize *= 2;
+        buf = BJAM_MALLOC( bufsize );
+    }
+    
+    if ( buf != static_buf )
+        BJAM_FREE( buf );
+
+    return result;
+#endif
+}
+
 
 #ifdef HAVE_PYTHON
 

src/engine/builtins.h

@@ -63,6 +63,7 @@ LIST *builtin_pad( FRAME * frame, int flags );
 LIST *builtin_precious( FRAME * frame, int flags );
 LIST *builtin_self_path( FRAME * frame, int flags );
 LIST *builtin_makedir( FRAME * frame, int flags );
+LIST *builtin_readlink( FRAME * frame, int flags );
 
 void backtrace( FRAME *frame );
 extern int last_update_now_status;

src/engine/filent.c

@@ -122,6 +122,19 @@ int file_collect_dir_content_( file_info_t * const d )
                 ff->is_file = !ff->is_dir;
                 ff->exists = 1;
                 timestamp_from_filetime( &ff->time, &finfo.ftLastWriteTime );
+                // Use the timestamp of the link target, not the link itself
+                // (i.e. stat instead of lstat)
+                if ( finfo.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT )
+                {
+                    HANDLE hLink = CreateFileA( pathname->value, 0, FILE_SHARE_READ, NULL, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL );
+                    BY_HANDLE_FILE_INFORMATION target_finfo[ 1 ];
+                    if ( hLink != INVALID_HANDLE_VALUE && GetFileInformationByHandle( hLink, target_finfo ) )
+                    {
+                        ff->is_file = target_finfo->dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY ? 0 : 1;
+                        ff->is_dir = target_finfo->dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY ? 1 : 0;
+                        timestamp_from_filetime( &ff->time, &target_finfo->ftLastWriteTime );
+                    }
+                }
             }
         }
         while ( FindNextFile( findHandle, &finfo ) );

src/engine/timestamp.h

@@ -14,7 +14,6 @@
 #include "object.h"
 
 #ifdef OS_NT
-# define WIN32_LEAN_AND_MEAN
 # include <windows.h>
 #endif