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OS/2 specific fixes related to SF bug # 1003471.

Browse source 
Also revise a related function to minimise file handle/pipe leakage
and improve reliability.
This commit is contained in:
Andrew MacIntyre 2004-12-12 08:30:51 +00:00
parent d0278ec97f
commit a4a8afb4e1
1 changed files with 65 additions and 66 deletions
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131
Modules/posixmodule.c
View file

@ -3248,86 +3248,85 @@ Open a pipe to/from a command returning a file object.");
static int
async_system(const char *command)
{
char *p, errormsg[256], args[1024];
RESULTCODES rcodes;
APIRET rc;
char *shell = getenv("COMSPEC");
if (!shell)
shell = "cmd";
char errormsg[256], args[1024];
RESULTCODES rcodes;
APIRET rc;
strcpy(args, shell);
p = &args[ strlen(args)+1 ];
strcpy(p, "/c ");
strcat(p, command);
p += strlen(p) + 1;
*p = '\0';
char *shell = getenv("COMSPEC");
if (!shell)
shell = "cmd";
rc = DosExecPgm(errormsg, sizeof(errormsg),
EXEC_ASYNC, /* Execute Async w/o Wait for Results */
args,
NULL, /* Inherit Parent's Environment */
&rcodes, shell);
return rc;
/* avoid overflowing the argument buffer */
if (strlen(shell) + 3 + strlen(command) >= 1024)
return ERROR_NOT_ENOUGH_MEMORY
args[0] = '\0';
strcat(args, shell);
strcat(args, "/c ");
strcat(args, command);
/* execute asynchronously, inheriting the environment */
rc = DosExecPgm(errormsg,
sizeof(errormsg),
EXEC_ASYNC,
args,
NULL,
&rcodes,
shell);
return rc;
}
static FILE *
popen(const char *command, const char *mode, int pipesize, int *err)
{
HFILE rhan, whan;
FILE *retfd = NULL;
APIRET rc = DosCreatePipe(&rhan, &whan, pipesize);
int oldfd, tgtfd;
HFILE pipeh[2];
APIRET rc;
if (rc != NO_ERROR) {
*err = rc;
return NULL; /* ERROR - Unable to Create Anon Pipe */
}
/* mode determines which of stdin or stdout is reconnected to
* the pipe to the child
*/
if (strchr(mode, 'r') != NULL) {
tgt_fd = 1; /* stdout */
} else if (strchr(mode, 'w')) {
tgt_fd = 0; /* stdin */
} else {
*err = ERROR_INVALID_ACCESS;
return NULL;
}
if (strchr(mode, 'r') != NULL) { /* Treat Command as a Data Source */
int oldfd = dup(1); /* Save STDOUT Handle in Another Handle */
/* setup the pipe
if ((rc = DosCreatePipe(&pipeh[0], &pipeh[1], pipesize)) != NO_ERROR) {
*err = rc;
return NULL;
}
DosEnterCritSec(); /* Stop Other Threads While Changing Handles */
close(1); /* Make STDOUT Available for Reallocation */
/* prevent other threads accessing stdio */
DosEnterCritSec();
if (dup2(whan, 1) == 0) { /* Connect STDOUT to Pipe Write Side */
DosClose(whan); /* Close Now-Unused Pipe Write Handle */
/* reconnect stdio and execute child */
oldfd = dup(tgtfd);
close(tgtfd);
if (dup2(pipeh[tgtfd], tgtfd) == 0) {
DosClose(pipeh[tgtfd]);
rc = async_system(command);
}
rc = async_system(command);
}
/* restore stdio */
dup2(oldfd, tgtfd);
close(oldfd);
dup2(oldfd, 1); /* Reconnect STDOUT to Original Handle */
DosExitCritSec(); /* Now Allow Other Threads to Run */
/* allow other threads access to stdio */
DosExitCritSec();
if (rc == NO_ERROR)
retfd = fdopen(rhan, mode); /* And Return Pipe Read Handle */
close(oldfd); /* And Close Saved STDOUT Handle */
return retfd; /* Return fd of Pipe or NULL if Error */
} else if (strchr(mode, 'w')) { /* Treat Command as a Data Sink */
int oldfd = dup(0); /* Save STDIN Handle in Another Handle */
DosEnterCritSec(); /* Stop Other Threads While Changing Handles */
close(0); /* Make STDIN Available for Reallocation */
if (dup2(rhan, 0) == 0) { /* Connect STDIN to Pipe Read Side */
DosClose(rhan); /* Close Now-Unused Pipe Read Handle */
rc = async_system(command);
}
dup2(oldfd, 0); /* Reconnect STDIN to Original Handle */
DosExitCritSec(); /* Now Allow Other Threads to Run */
if (rc == NO_ERROR)
retfd = fdopen(whan, mode); /* And Return Pipe Write Handle */
close(oldfd); /* And Close Saved STDIN Handle */
return retfd; /* Return fd of Pipe or NULL if Error */
} else {
*err = ERROR_INVALID_ACCESS;
return NULL; /* ERROR - Invalid Mode (Neither Read nor Write) */
}
/* if execution of child was successful return file stream */
if (rc == NO_ERROR)
return fdopen(pipeh[1 - tgtfd], mode);
else {
DosClose(pipeh[1 - tgtfd]);
*err = rc;
return NULL;
}
}
static PyObject *