for #367: extract the process from ffmpeg to exec programs.

trunk/src/app/srs_app_process.hpp

@@ -0,0 +1,99 @@
+/*
+ The MIT License (MIT)
+ 
+ Copyright (c) 2013-2015 SRS(simple-rtmp-server)
+ 
+ Permission is hereby granted, free of charge, to any person obtaining a copy of
+ this software and associated documentation files (the "Software"), to deal in
+ the Software without restriction, including without limitation the rights to
+ use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ the Software, and to permit persons to whom the Software is furnished to do so,
+ subject to the following conditions:
+ 
+ The above copyright notice and this permission notice shall be included in all
+ copies or substantial portions of the Software.
+ 
+ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#ifndef SRS_APP_PROCESS_HPP
+#define SRS_APP_PROCESS_HPP
+
+/*
+#include <srs_app_process.hpp>
+*/
+#include <srs_core.hpp>
+
+#include <string>
+#include <vector>
+
+/**
+ * to start and stop a process, cycle to restart the process when terminated.
+ * the usage:
+ *      process = new SrsProcess();
+ *      if ((ret = process->initialize(binary, argv)) != ERROR_SUCCESS) { return ret; }
+ *      if ((ret = process->start()) != ERROR_SUCCESS) { return ret; }
+ *      if ((ret = process->cycle()) != ERROR_SUCCESS) { return ret; }
+ *      process->fast_stop();
+ *      process->stop();
+ */
+class SrsProcess
+{
+private:
+    bool is_started;
+    // whether SIGTERM send but need to wait or SIGKILL.
+    bool fast_stopped;
+    pid_t pid;
+private:
+    std::string bin;
+    std::vector<std::string> params;
+public:
+    SrsProcess();
+    virtual ~SrsProcess();
+public:
+    /**
+     * whether process is already started.
+     */
+    virtual bool started();
+    /**
+     * initialize the process with binary and argv.
+     */
+    virtual int initialize(std::string binary, std::vector<std::string> argv);
+public:
+    /**
+     * start the process, ignore when already started.
+     */
+    virtual int start();
+    /**
+     * cycle check the process, update the state of process.
+     * @remark when process terminated(not started), user can restart it again by start().
+     */
+    virtual int cycle();
+    /**
+     * send SIGTERM then SIGKILL to ensure the process stopped.
+     * the stop will wait [0, SRS_PROCESS_QUIT_TIMEOUT_MS] depends on the
+     * process quit timeout.
+     * @remark use fast_stop before stop one by one, when got lots of process to quit.
+     */
+    virtual void stop();
+public:
+    /**
+     * the fast stop is to send a SIGTERM.
+     * for example, the ingesters owner lots of FFMPEG, it will take a long time
+     * to stop one by one, instead the ingesters can fast_stop all FFMPEG, then
+     * wait one by one to stop, it's more faster.
+     * @remark user must use stop() to ensure the ffmpeg to stopped.
+     * @remark we got N processes to stop, compare the time we spend,
+     *      when use stop without fast_stop, we spend maybe [0, SRS_PROCESS_QUIT_TIMEOUT_MS * N]
+     *      but use fast_stop then stop, the time is almost [0, SRS_PROCESS_QUIT_TIMEOUT_MS].
+     */
+    virtual void fast_stop();
+};
+
+#endif
+