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-rw-r--r--compat/waitpid.c93
1 files changed, 45 insertions, 48 deletions
diff --git a/compat/waitpid.c b/compat/waitpid.c
index 365d51e..0e9e6d6 100644
--- a/compat/waitpid.c
+++ b/compat/waitpid.c
@@ -1,18 +1,17 @@
/*
* waitpid.c --
*
- * This procedure emulates the POSIX waitpid kernel call on
- * BSD systems that don't have waitpid but do have wait3.
- * This code is based on a prototype version written by
- * Mark Diekhans and Karl Lehenbauer.
+ * This procedure emulates the POSIX waitpid kernel call on BSD systems
+ * that don't have waitpid but do have wait3. This code is based on a
+ * prototype version written by Mark Diekhans and Karl Lehenbauer.
*
* Copyright (c) 1993 The Regents of the University of California.
* Copyright (c) 1994 Sun Microsystems, Inc.
*
- * See the file "license.terms" for information on usage and redistribution
- * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
+ * See the file "license.terms" for information on usage and redistribution of
+ * this file, and for a DISCLAIMER OF ALL WARRANTIES.
*
- * RCS: @(#) $Id: waitpid.c,v 1.4 2004/04/06 22:25:48 dgp Exp $
+ * RCS: @(#) $Id: waitpid.c,v 1.5 2007/04/16 13:36:35 dkf Exp $
*/
#include "tclPort.h"
@@ -22,40 +21,37 @@
#endif
/*
- * A linked list of the following structures is used to keep track
- * of processes for which we received notification from the kernel,
- * but the application hasn't waited for them yet (this can happen
- * because wait may not return the process we really want). We
- * save the information here until the application finally does
- * wait for the process.
+ * A linked list of the following structures is used to keep track of
+ * processes for which we received notification from the kernel, but the
+ * application hasn't waited for them yet (this can happen because wait may
+ * not return the process we really want). We save the information here until
+ * the application finally does wait for the process.
*/
typedef struct WaitInfo {
- pid_t pid; /* Pid of process that exited. */
- WAIT_STATUS_TYPE status; /* Status returned when child exited
- * or suspended. */
- struct WaitInfo *nextPtr; /* Next in list of exited processes. */
+ pid_t pid; /* Pid of process that exited. */
+ WAIT_STATUS_TYPE status; /* Status returned when child exited or
+ * suspended. */
+ struct WaitInfo *nextPtr; /* Next in list of exited processes. */
} WaitInfo;
-static WaitInfo *deadList = NULL; /* First in list of all dead
- * processes. */
+static WaitInfo *deadList = NULL;
+ /* First in list of all dead processes. */
/*
*----------------------------------------------------------------------
*
* waitpid --
*
- * This procedure emulates the functionality of the POSIX
- * waitpid kernel call, using the BSD wait3 kernel call.
- * Note: it doesn't emulate absolutely all of the waitpid
- * functionality, in that it doesn't support pid's of 0
- * or < -1.
+ * This procedure emulates the functionality of the POSIX waitpid kernel
+ * call, using the BSD wait3 kernel call. Note: it doesn't emulate
+ * absolutely all of the waitpid functionality, in that it doesn't
+ * support pid's of 0 or < -1.
*
* Results:
- * -1 is returned if there is an error in the wait kernel call.
- * Otherwise the pid of an exited or suspended process is
- * returned and *statusPtr is set to the status value of the
- * process.
+ * -1 is returned if there is an error in the wait kernel call. Otherwise
+ * the pid of an exited or suspended process is returned and *statusPtr
+ * is set to the status value of the process.
*
* Side effects:
* None.
@@ -68,12 +64,12 @@ static WaitInfo *deadList = NULL; /* First in list of all dead
#endif
pid_t
-waitpid(pid, statusPtr, options)
- pid_t pid; /* The pid to wait on. Must be -1 or
- * greater than zero. */
- int *statusPtr; /* Where to store wait status for the
+waitpid(
+ pid_t pid, /* The pid to wait on. Must be -1 or greater
+ * than zero. */
+ int *statusPtr, /* Where to store wait status for the
* process. */
- int options; /* OR'ed combination of WNOHANG and
+ int options) /* OR'ed combination of WNOHANG and
* WUNTRACED. */
{
register WaitInfo *waitPtr, *prevPtr;
@@ -86,9 +82,9 @@ waitpid(pid, statusPtr, options)
}
/*
- * See if there's a suitable process that has already stopped or
- * exited. If so, remove it from the list of exited processes and
- * return its information.
+ * See if there's a suitable process that has already stopped or exited.
+ * If so, remove it from the list of exited processes and return its
+ * information.
*/
for (waitPtr = deadList, prevPtr = NULL; waitPtr != NULL;
@@ -111,12 +107,12 @@ waitpid(pid, statusPtr, options)
}
/*
- * Wait for any process to stop or exit. If it's an acceptable one
- * then return it to the caller; otherwise store information about it
- * in the list of exited processes and try again. On systems that
- * have only wait but not wait3, there are several situations we can't
- * handle, but we do the best we can (e.g. can still handle some
- * combinations of options by invoking wait instead of wait3).
+ * Wait for any process to stop or exit. If it's an acceptable one then
+ * return it to the caller; otherwise store information about it in the
+ * list of exited processes and try again. On systems that have only wait
+ * but not wait3, there are several situations we can't handle, but we do
+ * the best we can (e.g. can still handle some combinations of options by
+ * invoking wait instead of wait3).
*/
while (1) {
@@ -149,13 +145,13 @@ waitpid(pid, statusPtr, options)
return result;
/*
- * Can't return this info to caller. Save it in the list of
- * stopped or exited processes. Tricky point: first check for
- * an existing entry for the process and overwrite it if it
- * exists (e.g. a previously stopped process might now be dead).
+ * Can't return this info to caller. Save it in the list of stopped or
+ * exited processes. Tricky point: first check for an existing entry
+ * for the process and overwrite it if it exists (e.g. a previously
+ * stopped process might now be dead).
*/
- saveInfo:
+ saveInfo:
for (waitPtr = deadList; waitPtr != NULL; waitPtr = waitPtr->nextPtr) {
if (waitPtr->pid == result) {
waitPtr->status = status;
@@ -168,6 +164,7 @@ waitpid(pid, statusPtr, options)
waitPtr->nextPtr = deadList;
deadList = waitPtr;
- waitAgain: continue;
+ waitAgain:
+ continue;
}
}