diff options
Diffstat (limited to 'indra/llcommon/llprocess.h')
| -rw-r--r-- | indra/llcommon/llprocess.h | 63 |
1 files changed, 41 insertions, 22 deletions
diff --git a/indra/llcommon/llprocess.h b/indra/llcommon/llprocess.h index d005847e18..637b7e2f9c 100644 --- a/indra/llcommon/llprocess.h +++ b/indra/llcommon/llprocess.h @@ -58,12 +58,16 @@ typedef boost::shared_ptr<LLProcess> LLProcessPtr; * arguments. It also keeps track of whether the process is still running, and * can kill it if required. * + * In discussing LLProcess, we use the term "parent" to refer to this process + * (the process invoking LLProcess), versus "child" to refer to the process + * spawned by LLProcess. + * * LLProcess relies on periodic post() calls on the "mainloop" LLEventPump: an - * LLProcess object's Status won't update until the next "mainloop" tick. The - * viewer's main loop already posts to that LLEventPump once per iteration - * (hence the name). See indra/llcommon/tests/llprocess_test.cpp for an - * example of waiting for child-process termination in a standalone test - * context. + * LLProcess object's Status won't update until the next "mainloop" tick. For + * instance, the Second Life viewer's main loop already posts to an + * LLEventPump by that name once per iteration. See + * indra/llcommon/tests/llprocess_test.cpp for an example of waiting for + * child-process termination in a standalone test context. */ class LL_COMMON_API LLProcess: public boost::noncopyable { @@ -110,10 +114,10 @@ public: * pumping nonblocking I/O every frame. The expectation (at least * for stdout or stderr) is that the caller will listen for * incoming data and consume it as it arrives. It's important not - * to neglect such a pipe, because it's buffered in viewer memory. - * If you suspect the child may produce a great volume of output - * between viewer frames, consider directing the child to write to - * a filesystem file instead, then read the file later. + * to neglect such a pipe, because it's buffered in memory. If you + * suspect the child may produce a great volume of output between + * frames, consider directing the child to write to a filesystem + * file instead, then read the file later. * * - "tpipe": do not engage LLProcess machinery to monitor the * parent end of the pipe. A "tpipe" is used only to connect @@ -145,9 +149,14 @@ public: Optional<std::string> name; FileParam(const std::string& tp="", const std::string& nm=""): - type("type", tp), - name("name", nm) - {} + type("type"), + name("name") + { + // If caller wants to specify values, use explicit assignment to + // set them rather than initialization. + if (! tp.empty()) type = tp; + if (! nm.empty()) name = nm; + } }; /// Param block definition @@ -175,17 +184,28 @@ public: /// current working directory, if need it changed Optional<std::string> cwd; /// implicitly kill process on destruction of LLProcess object + /// (default true) Optional<bool> autokill; /** * Up to three FileParam items: for child stdin, stdout, stderr. * Passing two FileParam entries means default treatment for stderr, * and so forth. * + * @note LLInitParam::Block permits usage like this: + * @code + * LLProcess::Params params; + * ... + * params.files + * .add(LLProcess::FileParam()) // stdin + * .add(LLProcess::FileParam().type("pipe") // stdout + * .add(LLProcess::FileParam().type("file").name("error.log")); + * @endcode + * * @note While it's theoretically plausible to pass additional open * file handles to a child specifically written to expect them, our - * underlying implementation library doesn't support that. + * underlying implementation doesn't yet support that. */ - Multiple<FileParam> files; + Multiple<FileParam, AtMost<3> > files; /** * On child-process termination, if this LLProcess object still * exists, post LLSD event to LLEventPump with specified name (default @@ -217,9 +237,8 @@ public: static LLProcessPtr create(const LLSDOrParams& params); virtual ~LLProcess(); - // isRunning() isn't const because, when child terminates, it sets stored - // Status - bool isRunning(void); + /// Is child process still running? + bool isRunning() const; /** * State of child process @@ -252,11 +271,11 @@ public: }; /// Status query - Status getStatus(); + Status getStatus() const; /// English Status string query, for logging etc. - std::string getStatusString(); + std::string getStatusString() const; /// English Status string query for previously-captured Status - std::string getStatusString(const Status& status); + std::string getStatusString(const Status& status) const; /// static English Status string query static std::string getStatusString(const std::string& desc, const Status& status); @@ -311,7 +330,7 @@ public: * filesystem name for the specified pipe. Otherwise returns the empty * string. @see LLProcess::FileParam::type */ - std::string getPipeName(FILESLOT); + std::string getPipeName(FILESLOT) const; /// base of ReadPipe, WritePipe class LL_COMMON_API BasePipe @@ -419,7 +438,7 @@ public: * contain "data"="abcde". However, you may still read the entire * "abcdef" from get_istream(): this limit affects only the size of * the data posted with the LLSD event. If you don't call this method, - * all pending data will be posted. + * @em no data will be posted: the default is 0 bytes. */ virtual void setLimit(size_type limit) = 0; |