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Fix for file descriptors getting hammered by StartPiped if 100, 101 or 102 were open.

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Thulinma 2020-05-25 01:32:49 +02:00
parent d45e78387d
commit 67c0d6666f
1 changed files with 19 additions and 15 deletions
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34
lib/procs.cpp
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@ -325,34 +325,38 @@ pid_t Util::Procs::StartPiped(const char *const *argv, int *fdin, int *fdout, in
} }
pid = fork(); pid = fork();
if (pid == 0){// child if (pid == 0){// child
int ch_stdin = 0, ch_stdout = 0, ch_stderr = 0;
handler_set = false; handler_set = false;
if (!fdin){ if (!fdin){
dup2(devnull, 100); ch_stdin = dup(devnull);
}else if (*fdin == -1){ }else if (*fdin == -1){
close(pipein[1]); // close unused write end close(pipein[1]); // close unused write end
dup2(pipein[0], 100); ch_stdin = dup(pipein[0]);
close(pipein[0]); close(pipein[0]);
}else{ }else{
dup2(*fdin, 100); ch_stdin = dup(*fdin);
} }
while (ch_stdin < 3){ch_stdin = dup(ch_stdin);}
if (!fdout){ if (!fdout){
dup2(devnull, 101); ch_stdout = dup(devnull);
}else if (*fdout == -1){ }else if (*fdout == -1){
close(pipeout[0]); // close unused read end close(pipeout[0]); // close unused read end
dup2(pipeout[1], 101); ch_stdout = dup(pipeout[1]);
close(pipeout[1]); close(pipeout[1]);
}else{ }else{
dup2(*fdout, 101); ch_stdout = dup(*fdout);
} }
while (ch_stdout < 3){ch_stdout = dup(ch_stdout);}
if (!fderr){ if (!fderr){
dup2(devnull, 102); ch_stderr = dup(devnull);
}else if (*fderr == -1){ }else if (*fderr == -1){
close(pipeerr[0]); // close unused read end close(pipeerr[0]); // close unused read end
dup2(pipeerr[1], 102); ch_stderr = dup(pipeerr[1]);
close(pipeerr[1]); close(pipeerr[1]);
}else{ }else{
dup2(*fderr, 102); ch_stderr = dup(*fderr);
} }
while (ch_stderr < 3){ch_stderr = dup(ch_stderr);}
if (fdin && *fdin != -1){close(*fdin);} if (fdin && *fdin != -1){close(*fdin);}
if (fdout && *fdout != -1){close(*fdout);} if (fdout && *fdout != -1){close(*fdout);}
if (fderr && *fderr != -1){close(*fderr);} if (fderr && *fderr != -1){close(*fderr);}
@ -363,12 +367,12 @@ pid_t Util::Procs::StartPiped(const char *const *argv, int *fdin, int *fdout, in
close(*it); close(*it);
} }
//Black magic to make sure if 0/1/2 are not what we think they are, we end up with them not mixed up and weird. //Black magic to make sure if 0/1/2 are not what we think they are, we end up with them not mixed up and weird.
dup2(100, 0); dup2(ch_stdin, 0);
dup2(101, 1); dup2(ch_stdout, 1);
dup2(102, 2); dup2(ch_stderr, 2);
close(100); close(ch_stdout);
close(101); close(ch_stdin);
close(102); close(ch_stderr);
//There! Now we normalized our stdio //There! Now we normalized our stdio
// Because execvp requires a char* const* and we have a const char* const* // Because execvp requires a char* const* and we have a const char* const*
execvp(argv[0], (char *const *)argv); execvp(argv[0], (char *const *)argv);