Source/cmProcessTools.h

   1 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
   2    file Copyright.txt or https://cmake.org/licensing for details.  */
   3 #pragma once
   4
   5 #include "cmConfigure.h" // IWYU pragma: keep
   6
   7 #include <cstring>
   8 #include <iosfwd>
   9 #include <string>
  10 #include <vector>
  11
  12 #include "cmProcessOutput.h"
  13 #include "cmUVProcessChain.h"
  14
  15 /** \class cmProcessTools
  16  * \brief Helper classes for process output parsing
  17  *
  18  */
  19 class cmProcessTools
  20 {
  21 public:
  22   using Encoding = cmProcessOutput::Encoding;
  23   /** Abstract interface for process output parsers.  */
  24   class OutputParser
  25   {
  26   public:
  27     /** Process the given output data from a tool.  Processing may be
  28         done incrementally.  Returns true if the parser is interested
  29         in any more data and false if it is done.  */
  30     bool Process(const char* data, int length)
  31     {
  32       return this->ProcessChunk(data, length);
  33     }
  34     bool Process(const char* data)
  35     {
  36       return this->Process(data, static_cast<int>(strlen(data)));
  37     }
  38
  39     virtual ~OutputParser() = default;
  40
  41   protected:
  42     /** Implement in a subclass to process a chunk of data.  It should
  43         return true only if it is interested in more data.  */
  44     virtual bool ProcessChunk(const char* data, int length) = 0;
  45   };
  46
  47   /** Process output parser that extracts one line at a time.  */
  48   class LineParser : public OutputParser
  49   {
  50   public:
  51     /** Construct with line separation character and choose whether to
  52         ignore carriage returns.  */
  53     LineParser(char sep = '\n', bool ignoreCR = true);
  54
  55     /** Configure logging of lines as they are extracted.  */
  56     void SetLog(std::ostream* log, const char* prefix);
  57
  58   protected:
  59     std::ostream* Log = nullptr;
  60     const char* Prefix = nullptr;
  61     std::string Line;
  62     char Separator;
  63     char LineEnd = '\0';
  64     bool IgnoreCR;
  65     bool ProcessChunk(const char* data, int length) override;
  66
  67     /** Implement in a subclass to process one line of input.  It
  68         should return true only if it is interested in more data.  */
  69     virtual bool ProcessLine() = 0;
  70   };
  71
  72   /** Trivial line handler for simple logging.  */
  73   class OutputLogger : public LineParser
  74   {
  75   public:
  76     OutputLogger(std::ostream& log, const char* prefix = nullptr)
  77     {
  78       this->SetLog(&log, prefix);
  79     }
  80
  81   private:
  82     bool ProcessLine() override { return true; }
  83   };
  84
  85   /** Run a process and send output to given parsers.  */
  86   static std::vector<cmUVProcessChain::Status> RunProcess(
  87     cmUVProcessChainBuilder& builder, OutputParser* out,
  88     OutputParser* err = nullptr, Encoding encoding = cmProcessOutput::Auto);
  89 };