--- a/src/execmd.h
+++ b/src/execmd.h
@@ -17,35 +17,31 @@
#ifndef _EXECMD_H_INCLUDED_
#define _EXECMD_H_INCLUDED_
-#include <signal.h>
-
#include <string>
#include <vector>
#include <stack>
-#include "netcon.h"
-
-/**
- * Callback function object to advise of new data arrival, or just periodic
- * heartbeat if cnt is 0.
+/**
+ * Callback function object to advise of new data arrival, or just periodic
+ * heartbeat if cnt is 0.
*
* To interrupt the command, the code using ExecCmd should either
- * raise an exception inside newData() (and catch it in doexec's caller), or
- * call ExecCmd::setKill()
- *
+ * raise an exception inside newData() (and catch it in doexec's caller), or
+ * call ExecCmd::setKill()
+ *
*/
class ExecCmdAdvise {
- public:
+public:
virtual ~ExecCmdAdvise() {}
virtual void newData(int cnt) = 0;
};
-/**
+/**
* Callback function object to get more input data. Data has to be provided
- * in the initial input string, set it to empty to signify eof.
+ * into the initial input string, set it to empty to signify eof.
*/
class ExecCmdProvide {
- public:
+public:
virtual ~ExecCmdProvide() {}
virtual void newData() = 0;
};
@@ -55,126 +51,156 @@
* asynchronous io as appropriate for things to work).
*
* Input to the command can be provided either once in a parameter to doexec
- * or provided in chunks by setting a callback which will be called to
+ * or provided in chunks by setting a callback which will be called to
* request new data. In this case, the 'input' parameter to doexec may be
* empty (but not null)
*
* Output from the command is normally returned in a single string, but a
* callback can be set to be called whenever new data arrives, in which case
* it is permissible to consume the data and erase the string.
- *
+ *
* Note that SIGPIPE should be ignored and SIGCLD blocked when calling doexec,
* else things might fail randomly. (This is not done inside the class because
* of concerns with multithreaded programs).
*
*/
class ExecCmd {
- public:
- // Use vfork instead of fork. This must not be called in a multithreaded
- // program.
- static void useVfork(bool on)
- {
- o_useVfork = on;
- }
- /**
+public:
+ // Use vfork instead of fork. Our vfork usage is multithread-compatible as
+ // far as I can see, but just in case...
+ static void useVfork(bool on);
+
+ /**
* Add/replace environment variable before executing command. This must
* be called before doexec() to have an effect (possibly multiple
* times for several variables).
* @param envassign an environment assignment string ("name=value")
*/
- void putenv(const std::string &envassign);
- void putenv(const std::string &name, const std::string& value);
-
- /**
+ void putenv(const std::string& envassign);
+ void putenv(const std::string& name, const std::string& value);
+
+ /**
+ * Try to set a limit on child process vm size. This will use
+ * setrlimit() and RLIMIT_AS/VMEM if available. Parameter is in
+ * units of 2**10. Must be called before starting the command, default
+ * is inherit from parent.
+ */
+ void setrlimit_as(int mbytes);
+
+ /**
* Set function objects to call whenever new data is available or on
- * select timeout / whenever new data is needed to send. Must be called
- * before doexec()
- */
- void setAdvise(ExecCmdAdvise *adv) {m_advise = adv;}
- void setProvide(ExecCmdProvide *p) {m_provide = p;}
-
- /**
- * Set select timeout in milliseconds. The default is 1 S.
+ * select timeout. The data itself is stored in the output string.
+ * Must be set before calling doexec.
+ */
+ void setAdvise(ExecCmdAdvise *adv);
+ /*
+ * Set function object to call whenever new data is needed. The
+ * data should be stored in the input string. Must be set before
+ * calling doexec()
+ */
+ void setProvide(ExecCmdProvide *p);
+
+ /**
+ * Set select timeout in milliseconds. The default is 1 S.
* This is NOT a time after which an error will occur, but the period of
- * the calls to the cancellation check routine.
- */
- void setTimeout(int mS) {if (mS > 30) m_timeoutMs = mS;}
-
- /**
- * Set destination for stderr data. The default is to let it alone (will
+ * the calls to the advise routine (which normally checks for cancellation).
+ */
+ void setTimeout(int mS);
+
+ /**
+ * Set destination for stderr data. The default is to let it alone (will
* usually go to the terminal or to wherever the desktop messages go).
* There is currently no option to put stderr data into a program variable
* If the parameter can't be opened for writing, the command's
* stderr will be closed.
*/
- void setStderr(const std::string &stderrFile) {m_stderrFile = stderrFile;}
-
- /**
- * Execute command.
+ void setStderr(const std::string& stderrFile);
+
+ /**
+ * Execute command.
*
- * Both input and output can be specified, and asynchronous
+ * Both input and output can be specified, and asynchronous
* io (select-based) is used to prevent blocking. This will not
* work if input and output need to be synchronized (ie: Q/A), but
* works ok for filtering.
- * The function is exception-safe. In case an exception occurs in the
+ * The function is exception-safe. In case an exception occurs in the
* advise callback, fds and pids will be cleaned-up properly.
*
- * @param cmd the program to execute. This must be an absolute file name
+ * @param cmd the program to execute. This must be an absolute file name
* or exist in the PATH.
* @param args the argument vector (NOT including argv[0]).
* @param input Input to send TO the command.
* @param output Output FROM the command.
- * @return the exec ouput status (0 if ok), or -1
- */
- int doexec(const std::string &cmd, const std::vector<std::string>& args,
- const std::string *input = 0,
- std::string *output = 0);
+ * @return the exec output status (0 if ok), or -1
+ */
+ int doexec(const std::string& cmd, const std::vector<std::string>& args,
+ const std::string *input = 0,
+ std::string *output = 0);
/** Same as doexec but cmd and args in one vector */
- int doexec1(const std::vector<std::string>& args,
- const std::string *input = 0,
+ int doexec1(const std::vector<std::string>& args,
+ const std::string *input = 0,
std::string *output = 0) {
- if (args.empty())
+ if (args.empty()) {
return -1;
+ }
return doexec(args[0],
std::vector<std::string>(args.begin() + 1, args.end()),
input, output);
}
/*
- * The next four methods can be used when a Q/A dialog needs to be
+ * The next four methods can be used when a Q/A dialog needs to be
* performed with the command
*/
- int startExec(const std::string &cmd, const std::vector<std::string>& args,
- bool has_input, bool has_output);
+ int startExec(const std::string& cmd, const std::vector<std::string>& args,
+ bool has_input, bool has_output);
int send(const std::string& data);
int receive(std::string& data, int cnt = -1);
- int getline(std::string& data, int timeosecs = -1);
+
+ /** Read line. Will call back periodically to check for cancellation */
+ int getline(std::string& data);
+
+ /** Read line. Timeout after timeosecs seconds */
+ int getline(std::string& data, int timeosecs);
+
int wait();
- /** Wait with WNOHANG set.
- @return true if process exited, false else.
- @param O: status, the wait(2) call's status value */
+ /** Wait with WNOHANG set.
+ @return true if process exited, false else.
+ @param O: status, the wait(2) call's status value */
bool maybereap(int *status);
- pid_t getChildPid() {return m_pid;}
-
- /**
+ pid_t getChildPid();
+
+ /**
* Cancel/kill command. This can be called from another thread or
- * from the advise callback, which could also raise an exception to
- * accomplish the same thing
- */
- void setKill() {m_killRequest = true;}
-
- /**
- * Get rid of current process (become ready for start).
- */
- void zapChild() {setKill(); (void)wait();}
-
- ExecCmd()
- : m_advise(0), m_provide(0), m_timeoutMs(1000)
- {
- reset();
- }
+ * from the advise callback, which could also raise an exception
+ * to accomplish the same thing. In the owner thread, any I/O loop
+ * will exit at the next iteration, and the process will be waited for.
+ */
+ void setKill();
+
+ /**
+ * Get rid of current process (become ready for start). This will signal
+ * politely the process to stop, wait a moment, then terminate it. This
+ * is a blocking call.
+ */
+ void zapChild();
+
+ /**
+ * Request process termination (SIGTERM or equivalent). This returns
+ * immediately
+ */
+ bool requestChildExit();
+
+ enum ExFlags {EXF_NONE,
+ // Only does anything on windows. Used when starting
+ // a viewer. The default is to hide the window,
+ // because it avoids windows appearing and
+ // disappearing when executing stuff for previewing
+ EXF_SHOWWINDOW = 1,
+ };
+ ExecCmd(int flags = 0);
~ExecCmd();
/**
@@ -195,67 +221,40 @@
*/
static bool backtick(const std::vector<std::string> cmd, std::string& out);
- friend class ExecCmdRsrc;
- private:
- static bool o_useVfork;
-
- std::vector<std::string> m_env;
- ExecCmdAdvise *m_advise;
- ExecCmdProvide *m_provide;
- bool m_killRequest;
- int m_timeoutMs;
- std::string m_stderrFile;
- // Pipe for data going to the command
- int m_pipein[2];
- NetconP m_tocmd;
- // Pipe for data coming out
- int m_pipeout[2];
- NetconP m_fromcmd;
- // Subprocess id
- pid_t m_pid;
- // Saved sigmask
- sigset_t m_blkcld;
-
- // Reset internal state indicators. Any resources should have been
- // previously freed
- void reset() {
- m_killRequest = false;
- m_pipein[0] = m_pipein[1] = m_pipeout[0] = m_pipeout[1] = -1;
- m_pid = -1;
- sigemptyset(&m_blkcld);
- }
- // Child process code
- inline void dochild(const std::string &cmd, const char **argv,
- const char **envv, bool has_input, bool has_output);
- /* Copyconst and assignment private and forbidden */
- ExecCmd(const ExecCmd &) {}
- ExecCmd& operator=(const ExecCmd &) {return *this;};
-};
-
-
-/**
- * Rexecute self process with the same arguments.
+ class Internal;
+private:
+ Internal *m;
+ /* Copyconst and assignment are private and forbidden */
+ ExecCmd(const ExecCmd&) {}
+ ExecCmd& operator=(const ExecCmd&) {
+ return *this;
+ };
+};
+
+
+/**
+ * Rexecute self process with the same arguments.
*
* Note that there are some limitations:
- * - argv[0] has to be valid: an executable name which will be found in
- * the path when exec is called in the initial working directory. This is
+ * - argv[0] has to be valid: an executable name which will be found in
+ * the path when exec is called in the initial working directory. This is
* by no means guaranteed. The shells do this, but argv[0] could be an
* arbitrary string.
* - The initial working directory must be found and remain valid.
* - We don't try to do anything with fd 0,1,2. If they were changed by the
- * program, their initial meaning won't be the same as at the moment of the
+ * program, their initial meaning won't be the same as at the moment of the
* initial invocation.
- * - We don't restore the signals. Signals set to be blocked
+ * - We don't restore the signals. Signals set to be blocked
* or ignored by the program will remain ignored even if this was not their
* initial state.
* - The environment is also not restored.
* - Others system aspects ?
- * - Other program state: application-dependant. Any external cleanup
- * (temp files etc.) must be performed by the application. ReExec()
- * duplicates the atexit() function to make this easier, but the
+ * - Other program state: application-dependant. Any external cleanup
+ * (temp files etc.) must be performed by the application. ReExec()
+ * duplicates the atexit() function to make this easier, but the
* ReExec().atexit() calls must be done explicitely, this is not automatic
- *
- * In short, this is usable in reasonably controlled situations and if there
+ *
+ * In short, this is usable in reasonably controlled situations and if there
* are no security issues involved, but this does not perform miracles.
*/
class ReExec {
@@ -263,13 +262,14 @@
ReExec() {}
ReExec(int argc, char *argv[]);
void init(int argc, char *argv[]);
- int atexit(void (*function)(void))
- {
- m_atexitfuncs.push(function);
- return 0;
+ int atexit(void (*function)(void)) {
+ m_atexitfuncs.push(function);
+ return 0;
}
void reexec();
- const std::string& getreason() {return m_reason;}
+ const std::string& getreason() {
+ return m_reason;
+ }
// Insert new args into the initial argv. idx designates the place
// before which the new args are inserted (the default of 1
// inserts after argv[0] which would probably be an appropriate