cmFile.h/c : Added cmFileCopy() and cmFileBackup().

cmFile.c

@@ -2,9 +2,13 @@
 #include "cmGlobal.h"
 #include "cmRpt.h"
 #include "cmErr.h"
+#include "cmCtx.h"
 #include "cmFile.h"
+#include "cmFileSys.h"
 #include "cmMem.h"
 #include "cmMallocDebug.h"
+#include "cmLinkedHeap.h"
+#include "cmText.h"
 #include <sys/stat.h>
 cmFileH_t cmFileNullHandle = { NULL };
 
@@ -184,6 +188,7 @@ cmFileRC_t cmFileTell( cmFileH_t h, long* offsPtr )
   *offsPtr    = -1;
   cmFile_t* p = _cmFileHandleToPtr(h);
   errno       = 0;
+
   if((*offsPtr = ftell(p->fp)) == -1)
     return _cmFileError(p,kTellFailFileRC,errno,"File tell failed");
   return kOkFileRC;
@@ -360,6 +365,128 @@ cmChar_t* _cmFileFnToBuf( const cmChar_t* fn, cmRpt_t* rpt, unsigned nn, unsigne
   return buf;
 }
 
+cmFileRC_t    cmFileCopy( 
+    const cmChar_t* srcDir, 
+    const cmChar_t* srcFn, 
+    const cmChar_t* srcExt, 
+    const cmChar_t* dstDir, 
+    const cmChar_t* dstFn, 
+    const cmChar_t* dstExt,
+    cmErr_t*        err)
+{
+  cmFileRC_t      rc        = kOkFileRC;
+  unsigned        byteCnt   = 0;
+  cmChar_t*       buf       = NULL;
+  const cmChar_t* srcPathFn = NULL;
+  const cmChar_t* dstPathFn = NULL;
+
+  // form the source path fn
+  if((srcPathFn = cmFsMakeFn(srcDir,srcFn,srcExt,NULL)) == NULL )
+  {
+    rc = cmErrMsg(err,kFileSysFailFileRC,"The soure file name for dir:%s name:%s ext:%s could not be formed.",cmStringNullGuard(srcDir),cmStringNullGuard(srcFn),cmStringNullGuard(srcExt));
+    goto errLabel;
+  }
+
+  // form the dest path fn
+  if((dstPathFn = cmFsMakeFn(dstDir,dstFn,dstExt,NULL)) == NULL )
+  {
+    rc = cmErrMsg(err,kFileSysFailFileRC,"The destination file name for dir:%s name:%s ext:%s could not be formed.",cmStringNullGuard(dstDir),cmStringNullGuard(dstFn),cmStringNullGuard(dstExt));
+    goto errLabel;
+  }
+
+  // verify that the source exists
+  if( cmFsIsFile(srcPathFn) == false )
+  {
+    rc = cmErrMsg(err,kOpenFailFileRC,"The source file '%s' does not exist.",cmStringNullGuard(srcPathFn));
+    goto errLabel;
+  }
+
+  // read the source file into a buffer
+  if((buf = cmFileFnToBuf(srcPathFn,err->rpt,&byteCnt)) == NULL )
+    rc = cmErrMsg(err,kReadFailFileRC,"Attempt to fill a buffer from '%s' failed.",cmStringNullGuard(srcPathFn));
+  else
+  {
+    // write the file to the output file
+    if( cmFileFnWrite(dstPathFn,err->rpt,buf,byteCnt) != kOkFileRC )
+      rc = cmErrMsg(err,kWriteFailFileRC,"An attempt to write a buffer to '%s' failed.",cmStringNullGuard(dstPathFn));    
+  }
+
+ errLabel:
+  // free the buffer
+  cmMemFree(buf);
+  cmFsFreeFn(srcPathFn);
+  cmFsFreeFn(dstPathFn);
+  return rc;
+
+}
+
+cmFileRC_t cmFileBackup( const cmChar_t* dir, const cmChar_t* name, const cmChar_t* ext, cmErr_t* err )
+{
+  cmFileRC_t      rc      = kOkFileRC;
+  cmChar_t*       newName = NULL;
+  const cmChar_t* newFn   = NULL;
+  unsigned        n       = 0;
+  const cmChar_t* srcFn   = NULL;
+
+  // form the name of the backup file
+  if((srcFn = cmFsMakeFn(dir,name,ext,NULL)) == NULL )
+  {
+    rc = cmErrMsg(err,kFileSysFailFileRC,"Backup source file name formation failed.");
+    goto errLabel;
+  }
+
+  // if the src file does not exist then there is nothing to do
+  if( cmFsIsFile(srcFn) == false )
+    return rc;
+
+  // break the source file name up into dir/fn/ext.
+  cmFileSysPathPart_t* pp = NULL;
+  if((pp = cmFsPathParts(srcFn)) == NULL || pp->fnStr==NULL)
+  {
+    rc = cmErrMsg(err,kFileSysFailFileRC,"The file name '%s' could not be parsed into its parts.",cmStringNullGuard(srcFn));
+    goto errLabel;
+  }
+
+  // iterate until a unique file name is found
+  for(n=0; 1; ++n)
+  {
+    cmFsFreeFn(newFn);
+
+    // generate a new file name
+    newName = cmTsPrintfP(newName,"%s_%i",pp->fnStr,n);
+    
+    // form the new file name into a complete path
+    if((newFn = cmFsMakeFn(pp->dirStr,newName,pp->extStr,NULL)) == NULL )
+    {
+      rc = cmErrMsg(err,kFileSysFailFileRC,"A backup file name could not be formed for the file '%s'.",cmStringNullGuard(newName));
+      goto errLabel;
+    }
+
+    // if the new file name is not already in use ...
+    if( cmFsIsFile(newFn) == false )
+    {
+      // .. then duplicate the file
+      if((rc = cmFileCopy(srcFn,NULL,NULL,newFn,NULL,NULL,err)) != kOkFileRC )
+        rc = cmErrMsg(err,rc,"The file '%s' could not be duplicated as '%s'.",cmStringNullGuard(srcFn),cmStringNullGuard(newFn));
+
+      break;
+    }
+
+
+  }
+
+ errLabel:
+
+  cmFsFreeFn(srcFn);
+  cmFsFreeFn(newFn);
+  cmMemFree(newName);
+  cmFsFreePathParts(pp);
+
+  return rc;
+
+}
+
+
 cmChar_t*  cmFileToBuf( cmFileH_t h, unsigned* bufByteCntPtr )
 { return _cmFileToBuf(h,0,bufByteCntPtr); }
 

cmFile.h

@@ -27,7 +27,9 @@ extern "C" {
     kHandleInvalidFileRC,
     kStatFailFileRC,
     kBufAllocFailFileRC,
-    kBufTooSmallFileRC
+    kBufTooSmallFileRC,
+    kFileSysFailFileRC,
+
   };
 
   typedef unsigned   cmFileRC_t;
@@ -117,6 +119,28 @@ extern "C" {
   // 'rpt' is the report object to use for error reporting.
   cmChar_t*  cmFileFnToBuf( const cmChar_t* fn, cmRpt_t* rpt, unsigned* bufByteCntPtr );
 
+
+  // Copy the file named in srcDir/srcFn/srcExt to a file named dstDir/dstFn/dstExt.
+  // Note that srcExt/dstExt may be set to NULL if the file extension is included
+  // in srcFn/dstFn.  Likewise srcFn/dstFn may be set to NULL if the file name
+  // is included in srcDir/dstDir.
+  cmFileRC_t    cmFileCopy( 
+    const cmChar_t* srcDir, 
+    const cmChar_t* srcFn, 
+    const cmChar_t* srcExt, 
+    const cmChar_t* dstDir, 
+    const cmChar_t* dstFn, 
+    const cmChar_t* dstExt,
+    cmErr_t*        err);
+
+
+  // This function creates a backup copy of the file 'fn' by duplicating it into
+  // a file named fn_#.ext where # is an integer which makes the file name unique.
+  // The integers chosen with zero and are incremented until an
+  // unused file name is found in the same directory as 'fn'.
+  // If the file identified by 'fn' is not found then the function returns quietly.
+  cmFileRC_t cmFileBackup( const cmChar_t* dir, const cmChar_t* name, const cmChar_t* ext, cmErr_t* err );
+  
   // Allocate and fill a zero terminated string from a file.
   // Set *bufByteCntPtr to count of bytes read into the buffer.=
   // (the buffer memory size is one byte larger to account for the terminating zero)