Added support for reading configuration files

Configuration file is read as a response file in which file names in
the nested constructs `@file` are resolved relative to the directory
where the including file resides. Lines in which the first non-whitespace
character is '#' are considered as comments and are skipped. Trailing
backslashes are used to concatenate lines in the same way as they
are used in shell scripts.

Differential Revision: https://reviews.llvm.org/D24926

llvm-svn: 321586

1 files changed, 27 insertions, 0 deletions

diff --git a/llvm/include/llvm/Support/CommandLine.h b/llvm/include/llvm/Support/CommandLine.h
index d1901db7c68..f043c112861 100644
--- a/llvm/include/llvm/Support/CommandLine.h
+++ b/llvm/include/llvm/Support/CommandLine.h
@@ -1862,6 +1862,33 @@ using TokenizerCallback = void (*)(StringRef Source, StringSaver &Saver,
                                    SmallVectorImpl<const char *> &NewArgv,
                                    bool MarkEOLs);
 
+/// Tokenizes content of configuration file.
+///
+/// \param [in] Source The string representing content of config file.
+/// \param [in] Saver Delegates back to the caller for saving parsed strings.
+/// \param [out] NewArgv All parsed strings are appended to NewArgv.
+/// \param [in] MarkEOLs Added for compatibility with TokenizerCallback.
+///
+/// It works like TokenizeGNUCommandLine with ability to skip comment lines.
+///
+void tokenizeConfigFile(StringRef Source, StringSaver &Saver,
+                        SmallVectorImpl<const char *> &NewArgv,
+                        bool MarkEOLs = false);
+
+/// Reads command line options from the given configuration file.
+///
+/// \param [in] CfgFileName Path to configuration file.
+/// \param [in] Saver  Objects that saves allocated strings.
+/// \param [out] Argv Array to which the read options are added.
+/// \return true if the file was successfully read.
+///
+/// It reads content of the specified file, tokenizes it and expands "@file"
+/// commands resolving file names in them relative to the directory where
+/// CfgFilename resides.
+///
+bool readConfigFile(StringRef CfgFileName, StringSaver &Saver,
+                    SmallVectorImpl<const char *> &Argv);
+
 /// \brief Expand response files on a command line recursively using the given
 /// StringSaver and tokenization strategy.  Argv should contain the command line
 /// before expansion and will be modified in place. If requested, Argv will