Intermediate work, checked in for safekeeping as I pick up working on this again.

[pdclib] / platform / example / functions / _PDCLIB / open.c

diff --git a/platform/example/functions/_PDCLIB/open.c b/platform/example/functions/_PDCLIB/open.c
index f7d7778a9e59085c25891fc6d88bcf7c566ef85f..fc82485aec2d730b3505ee6e3e655e1c83faa11b 100644 (file)
--- a/platform/example/functions/_PDCLIB/open.c
+++ b/platform/example/functions/_PDCLIB/open.c
@@ -20,14 +20,12 @@
 #include <fcntl.h>
 #include <unistd.h>
 
-_PDCLIB_fd_t _PDCLIB_open( char const * const filename, unsigned int mode )
+int _PDCLIB_open( char const * const filename, unsigned int mode )
 {
-    /* FIXME: THIS IS NOT TO BE USED OUT-OF-THE-BOX.
-       It is a proof-of-concept implementation. E.g. a stream may only be fully
-       buffered IF IT CAN BE DETERMINED NOT TO REFER TO AN INTERACTIVE DEVICE.
-       This logic is not represented here, as this is the EXAMPLE platform, and
-       actual platform overlays may differ widely. Another point is the value
-       for permissions being hardcoded to 0664 for file creations.
+    /* This is an example implementation of _PDCLIB_open() fit for use with
+       POSIX kernels.
+       FIXME: The permissions of newly created files should not be hardcoded
+       here.
     */
     int osmode;
     switch ( mode & ~_PDCLIB_FBIN )
@@ -39,7 +37,7 @@ _PDCLIB_fd_t _PDCLIB_open( char const * const filename, unsigned int mode )
             osmode = O_WRONLY | O_CREAT | O_TRUNC;
             break;
         case _PDCLIB_FAPPEND: /* "a" */
-            osmode = O_APPEND | O_CREAT;
+            osmode = O_WRONLY | O_APPEND | O_CREAT;
             break;
         case _PDCLIB_FREAD | _PDCLIB_FRW: /* "r+" */
             osmode = O_RDWR;
@@ -69,20 +67,68 @@ _PDCLIB_fd_t _PDCLIB_open( char const * const filename, unsigned int mode )
 #include <_PDCLIB_test.h>
 
 #include <stdlib.h>
+#include <string.h>
+
+#include <errno.h>
 
 int main( void )
 {
     /* This testdriver assumes POSIX, i.e. _PDCLIB_fd_t being int and being
        incremented by one on each successful open.
     */
-    _PDCLIB_fd_t fh;
-    TESTCASE( _PDCLIB_open( "testfile2", _PDCLIB_FREAD ) == _PDCLIB_NOHANDLE );
-    TESTCASE( ( fh = _PDCLIB_open( "testfile1", _PDCLIB_FWRITE ) ) != _PDCLIB_NOHANDLE );
+    int fh;
+    char buffer[ 10 ];
+    /* Trying to read non-existent file. */
+    TESTCASE( _PDCLIB_open( "testfile", _PDCLIB_FREAD ) == _PDCLIB_NOHANDLE );
+    /* Writing to file, trying to read from it. */
+    TESTCASE( ( fh = _PDCLIB_open( "testfile", _PDCLIB_FWRITE ) ) != _PDCLIB_NOHANDLE );
+    TESTCASE( write( fh, "test", 4 ) == 4 );
+    TESTCASE( lseek( fh, 0, SEEK_SET ) == 0 );
+    TESTCASE( read( fh, buffer, 4 ) == -1 );
+    TESTCASE( _PDCLIB_close( fh ) == 0 );
+    /* Reading from file, trying to write to it. */
+    TESTCASE( ( fh = _PDCLIB_open( "testfile", _PDCLIB_FREAD ) ) != _PDCLIB_NOHANDLE );
+    TESTCASE( write( fh, "test", 4 ) == -1 );
+    TESTCASE( _PDCLIB_close( fh ) == 0 );
+    /* Appending to file, trying to read from it. */
+    TESTCASE( ( fh = _PDCLIB_open( "testfile", _PDCLIB_FAPPEND ) ) != _PDCLIB_NOHANDLE );
+    TESTCASE( write( fh, "app", 3 ) == 3 );
+    TESTCASE( lseek( fh, 0, SEEK_SET ) == 0 );
+    TESTCASE( read( fh, buffer, 10 ) == -1 );
+    TESTCASE( write( fh, "end", 3 ) == 3 );
+    TESTCASE( _PDCLIB_close( fh ) == 0 );
+    /* Reading and writing from file ("r+"). */
+    TESTCASE( ( fh = _PDCLIB_open( "testfile", _PDCLIB_FREAD | _PDCLIB_FRW ) ) != _PDCLIB_NOHANDLE );
+    TESTCASE( read( fh, buffer, 10 ) == 10 );
+    TESTCASE( memcmp( buffer, "testappend", 10 ) == 0 );
+    TESTCASE( lseek( fh, 0, SEEK_SET ) == 0 );
+    TESTCASE( write( fh, "wedo", 4 ) == 4 );
+    TESTCASE( lseek( fh, 0, SEEK_SET ) == 0 );
+    TESTCASE( read( fh, buffer, 10 ) == 10 );
+    TESTCASE( memcmp( buffer, "wedoappend", 10 ) == 0 );
+    TESTCASE( _PDCLIB_close( fh ) == 0 );
+    /* Writing and reading from file ("w+"). */
+    TESTCASE( ( fh = _PDCLIB_open( "testfile", _PDCLIB_FWRITE | _PDCLIB_FRW ) ) != _PDCLIB_NOHANDLE );
     TESTCASE( write( fh, "test", 4 ) == 4 );
-    TESTCASE( close( fh ) == 0 );
-    TESTCASE( _PDCLIB_open( "testfile1", _PDCLIB_FREAD ) != _PDCLIB_NOHANDLE );
-    system( "rm testfile1" );
+    TESTCASE( lseek( fh, 1, SEEK_SET ) == 1 );
+    TESTCASE( read( fh, buffer, 2 ) == 2 );
+    TESTCASE( memcmp( buffer, "es", 2 ) == 0 );
+    TESTCASE( write( fh, "sie", 3 ) == 3 );
+    TESTCASE( lseek( fh, 0, SEEK_SET ) == 0 );
+    TESTCASE( read( fh, buffer, 6 ) == 6 );
+    TESTCASE( memcmp( buffer, "tessie", 6 ) == 0 );
+    TESTCASE( _PDCLIB_close( fh ) == 0 );
+    /* Appending and reading from file ("a+"). */
+    TESTCASE( ( fh = _PDCLIB_open( "testfile", _PDCLIB_FAPPEND | _PDCLIB_FRW ) ) != _PDCLIB_NOHANDLE );
+    TESTCASE( write( fh, "baby", 4 ) == 4 );
+    TESTCASE( lseek( fh, 0, SEEK_SET ) == 0 );
+    TESTCASE( read( fh, buffer, 10 ) == 10 );
+    TESTCASE( memcmp( buffer, "tessiebaby", 10 ) == 0 );
+    TESTCASE( _PDCLIB_close( fh ) == 0 );
+    /* Cleaning up. */
+    system( "rm testfile" );
     return TEST_RESULTS;
 }
 
 #endif
+