Experimental version of waitpid()
git-svn-id: https://nuttx.svn.sourceforge.net/svnroot/nuttx/trunk@3359 7fd9a85b-ad96-42d3-883c-3090e2eb8679
This commit is contained in:
patacongo
parent
583fe718e2
commit
0d42de9829
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@ -86,7 +86,7 @@ vector_isr\intno:
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cli /* Disable interrupts firstly. */
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push $0 /* Push a dummy error code. */
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push $\intno /* Push the interrupt number. */
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jmp isr_common /* Go to the common handler code. */
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jmp isr_common /* Go to the common ISR handler code. */
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.endm
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/* This macro creates a stub for an ISR which passes it's own
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@ -98,7 +98,7 @@ vector_isr\intno:
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vector_isr\intno:
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cli /* Disable interrupts firstly. */
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push $\intno /* Push the interrupt number. */
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jmp isr_common /* Go to the common handler code. */
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jmp isr_common /* Go to the common ISR handler code. */
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.endm
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/* This macro creates a stub for an IRQ - the first parameter is
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@ -111,7 +111,7 @@ vector_irq\irqno:
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cli /* Disable interrupts firstly. */
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push $0 /* Push a dummy error code. */
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push $\intno /* Push the interrupt number. */
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jmp isr_common /* Go to the common handler code. */
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jmp irq_common /* Go to the common IRQ handler code. */
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.endm
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/****************************************************************************
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@ -9,13 +9,14 @@ Contents
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* QEMU
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- Building QEMU
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- Cygwin Build Problems
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- Running QEMU
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- Cygwin Build Problems
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- Running QEMU
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* Toolchains
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- Cygwin Buildroot Toolchain
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- Buildroot Instructions
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- Buildroot Instructions
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* Configurations
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- ostest
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- nsh
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QEMU
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====
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@ -47,18 +48,18 @@ Cygwin Build Problems
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Workaround:
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None known. It does not seem possible to build QEMU using the Cygwin gcc.
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I tried editing configure. Removing the following line will allow QEMU to
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configure:
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I tried editing configure. Removing the following line will allow QEMU to
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configure:
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QEMU_CFLAGS="-mno-cygwin $QEMU_CFLAGS"
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However, it then fails later during the compilation phase.
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However, it then fails later during the compilation phase.
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Recommendation:
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1. Google for "qemu windows download" and download some pre-built QEMU
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binaries. I found 0.14.0 here: http://dietpc.org/windows/qemu/, or
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2. Try building QEMU with MingGW (I understand that this is difficult).
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binaries. I found 0.14.0 here: http://dietpc.org/windows/qemu/, or
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2. Try building QEMU with MingGW (I understand that this is difficult).
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NOTE: As of this writing, I have not been successful getting ANY pre-built
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version of QEMU to work successful; they all fail immediately with
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@ -135,3 +136,13 @@ ostest
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cd <nuttx-directory>/tools
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./configure.sh qemu-i486/ostest
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nsh
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---
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Configures the NuttShell (nsh) located at examples/nsh. This
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configuration may be selected as follows:
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cd <nuttx-directory>/tools
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./configure.sh qemu-i486/nsh
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@ -1,7 +1,7 @@
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/********************************************************************************
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* nuttx/sched.h
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*
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* Copyright (C) 2007-2010 Gregory Nutt. All rights reserved.
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* Copyright (C) 2007-2011 Gregory Nutt. All rights reserved.
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* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
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*
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* Redistribution and use in source and binary forms, with or without
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@ -178,6 +178,10 @@ struct _TCB
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start_t start; /* Thread start function */
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entry_t entry; /* Entry Point into the thread */
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exitfunc_t exitfunc; /* Called if exit is called. */
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#ifdef CONFIG_SCHED_WAITPID /* Experimental */
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sem_t exitsem; /* Support for waitpid */
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int *stat_loc; /* Location to return exit status */
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#endif
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uint8_t sched_priority; /* Current priority of the thread */
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#ifdef CONFIG_PRIORITY_INHERITANCE
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# if CONFIG_SEM_NNESTPRIO > 0
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@ -152,6 +152,12 @@ typedef uint16_t ino_t;
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typedef int pid_t;
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/* id_t is a general identifier that can be used to contain at least a pid_t,
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* uid_t, or gid_t.
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*/
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typedef unsigned int id_t;
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/* blkcnt_t and off_t are signed integer types.
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*
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* blkcnt_t is used for file block counts.
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@ -0,0 +1,118 @@
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/****************************************************************************
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* include/sys/wait.h
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*
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* Copyright (C) 2011 Gregory Nutt. All rights reserved.
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* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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*
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in
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* the documentation and/or other materials provided with the
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* distribution.
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* 3. Neither the name NuttX nor the names of its contributors may be
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* used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
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* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
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* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
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* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
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* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.
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*
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****************************************************************************/
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#ifndef __INCLUDE_SYS_WAIT_H
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#define __INCLUDE_SYS_WAIT_H
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/****************************************************************************
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* Included Files
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****************************************************************************/
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#include <sys/types.h>
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#include <signal.h>
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#ifdef CONFIG_SCHED_WAITPID
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/****************************************************************************
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* Pre-Processor Definitions
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****************************************************************************/
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/* The following are provided for analysis of returned status values.
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* Encoded is as follows as 2 bytes of info(MS) then two bytes of code (LS).
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* Code:
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* 0 - Child has exited, info is the exit code.
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* Other values - Not implemented
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*/
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#define WEXITSTATUS(s) (((s) >> 8) & 0xff)/* Return exit status */
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#define WIFEXITED(s) (((s) & 0xff) == 0) /* True: Child exited normally */
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#define WIFCONTINUED(s) (false) /* True: Child has been continued */
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#define WIFSIGNALED(s) (false) /* True: Child exited due to uncaught signal */
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#define WIFSTOPPED(s) (false) /* True: Child is currently stopped */
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#define WSTOPSIG(s) (false) /* Return signal number that caused process to stop */
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#define WTERMSIG(s) (false) /* Return signal number that caused process to terminate */
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/* The following symbolic constants are possible values for the options
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* argument to waitpi(1) (1) and/or waitid() (2),
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*/
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#define WCONTINUED (1 << 0) /* Status for child that has been continued (1)(2) */
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#define WNOHANG (1 << 1) /* Do not wait if status not available (1) */
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#define WUNTRACED (1 << 2) /* Report status of stopped child process (1) */
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#define WEXITED (1 << 3) /* Wait for processes that have exited (2) */
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#define WSTOPPED (1 << 4) /* Status for child stopped on signal (2) */
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#define WNOHANG (1 << 5) /* Return immediately if there are no children (2) */
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#define WNOWAIT (1 << 6) /* Keep the process in a waitable state (2) */
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/****************************************************************************
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* Public Type Definitions
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****************************************************************************/
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#ifndef __ASSEMBLY__
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enum idtype_e
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{
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P_PID = 1,
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P_GID = 2,
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P_ALL = 3
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};
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typedef enum idtype_e idtype_t;
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/****************************************************************************
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* Public Function Prototypes
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****************************************************************************/
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#undef EXTERN
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#if defined(__cplusplus)
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#define EXTERN extern "C"
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extern "C" {
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#else
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#define EXTERN extern
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#endif
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EXTERN pid_t wait(int *stat_loc);
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EXTERN int waitid(idtype_t idtype, id_t id, siginfo_t *siginfo, int options);
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EXTERN pid_t waitpid(pid_t pid, int *stat_loc, int options);
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#undef EXTERN
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#if defined(__cplusplus)
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}
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#endif
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#endif /* __ASSEMBLY__ */
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#endif /* CONFIG_SCHED_WAITPID */
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#endif /* __INCLUDE_SYS_WAIT_H */
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@ -1,7 +1,7 @@
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############################################################################
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# sched/Makefile
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#
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# Copyright (C) 2007-2010 Gregory Nutt. All rights reserved.
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# Copyright (C) 2007-2011 Gregory Nutt. All rights reserved.
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# Author: Gregory Nutt <spudmonkey@racsa.co.cr>
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#
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# Redistribution and use in source and binary forms, with or without
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@ -58,6 +58,9 @@ SCHED_SRCS = sched_setparam.c sched_setpriority.c sched_getparam.c \
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ifeq ($(CONFIG_PRIORITY_INHERITANCE),y)
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SCHED_SRCS += sched_reprioritize.c
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endif
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ifeq ($(CONFIG_SCHED_WAITPID),y)
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SCHED_SRCS += sched_waitpid.c
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endif
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ENV_SRCS = env_getenvironptr.c env_dup.c env_share.c env_release.c \
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env_findvar.c env_removevar.c \
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@ -1,7 +1,7 @@
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/****************************************************************************
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* sched/exit.c
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*
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* Copyright (C) 2007, 2008 Gregory Nutt. All rights reserved.
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* Copyright (C) 2007, 2008, 2011 Gregory Nutt. All rights reserved.
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* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
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*
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* Redistribution and use in source and binary forms, with or without
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@ -93,6 +93,10 @@ void exit(int status)
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{
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_TCB *tcb = (_TCB*)g_readytorun.head;
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/* Only the lower 8 bits of the exit status are used */
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status &= 0xff;
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/* Flush all streams (File descriptors will be closed when
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* the TCB is deallocated.
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*/
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@ -101,6 +105,29 @@ void exit(int status)
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(void)lib_flushall(tcb->streams);
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#endif
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/* Wakeup any tasks waiting for this task to exit */
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#ifdef CONFIG_SCHED_WAITPID /* Experimental */
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while (tcb->exitsem.semcount < 0)
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{
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/* "If more than one thread is suspended in waitpid() awaiting
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* termination of the same process, exactly one thread will return
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* the process status at the time of the target process termination."
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* Hmmm.. what do we return to the others?
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*/
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if (tcb->stat_loc)
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{
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*tcb->stat_loc = status << 8;
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tcb->stat_loc = NULL;
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}
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/* Wake up the thread */
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sem_post(&tcb->exitsem);
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}
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#endif
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/* If an exit function was registered, call it now. */
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if (tcb->exitfunc) {
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@ -108,6 +135,7 @@ void exit(int status)
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(*tcb->exitfunc)();
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} /* end if */
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/* Then "really" exit */
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_exit(status & 0377);
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_exit(status);
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}
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@ -0,0 +1,252 @@
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/*****************************************************************************
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* sched/sched_waitpid.c
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*
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* Copyright (C) 2011 Gregory Nutt. All rights reserved.
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* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
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*
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* Redistribution and use in source and binary forms, with or without
|
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* modification, are permitted provided that the following conditions
|
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* are met:
|
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*
|
||||
* 1. Redistributions of source code must retain the above copyright
|
||||
* notice, this list of conditions and the following disclaimer.
|
||||
* 2. Redistributions in binary form must reproduce the above copyright
|
||||
* notice, this list of conditions and the following disclaimer in
|
||||
* the documentation and/or other materials provided with the
|
||||
* distribution.
|
||||
* 3. Neither the name NuttX nor the names of its contributors may be
|
||||
* used to endorse or promote products derived from this software
|
||||
* without specific prior written permission.
|
||||
*
|
||||
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
||||
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
||||
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
|
||||
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
|
||||
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
|
||||
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
|
||||
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
|
||||
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
|
||||
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
||||
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
|
||||
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
||||
* POSSIBILITY OF SUCH DAMAGE.
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||||
*
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*****************************************************************************/
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/*****************************************************************************
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* Included Files
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*****************************************************************************/
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#include <nuttx/config.h>
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#include <sys/wait.h>
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#include <semaphore.h>
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#include <errno.h>
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#include <nuttx/sched.h>
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#include "os_internal.h"
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#ifdef CONFIG_SCHED_WAITPID /* Experimental */
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/*****************************************************************************
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* Private Functions
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*****************************************************************************/
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/*****************************************************************************
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* Public Functions
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*****************************************************************************/
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/*****************************************************************************
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* Function: sched_waitpid
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*
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* Description:
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*
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* The waitpid() functions will obtain status information pertaining to one
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* of the caller's child processes. The waitpid() function will suspend
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* execution of the calling thread until status information for one of the
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* terminated child processes of the calling process is available, or until
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* delivery of a signal whose action is either to execute a signal-catching
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* function or to terminate the process. If more than one thread is suspended
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* in waitpid() awaiting termination of the same process, exactly one thread
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* will return the process status at the time of the target process
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* termination. If status information is available prior to the call to
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* waitpid(), return will be immediate.
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*
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* The pid argument specifies a set of child processes for which status is
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* requested. The waitpid() function will only return the status of a child
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* process from this set:
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*
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* - If pid is equal to (pid_t)-1, status is requested for any child process.
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* In this respect, waitpid() is then equivalent to wait().
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* - If pid is greater than 0, it specifies the process ID of a single child
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* process for which status is requested.
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* - If pid is 0, status is requested for any child process whose process
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* group ID is equal to that of the calling process.
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* - If pid is less than (pid_t)-1, status is requested for any child process
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* whose process group ID is equal to the absolute value of pid.
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*
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* The options argument is constructed from the bitwise-inclusive OR of zero
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* or more of the following flags, defined in the <sys/wait.h> header:
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*
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* WCONTINUED - The waitpid() function will report the status of any
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* continued child process specified by pid whose status has not been
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* reported since it continued from a job control stop.
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* WNOHANG - The waitpid() function will not suspend execution of the
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* calling thread if status is not immediately available for one of the
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* child processes specified by pid.
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* WUNTRACED - The status of any child processes specified by pid that are
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* stopped, and whose status has not yet been reported since they stopped,
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* will also be reported to the requesting process.
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*
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* If the calling process has SA_NOCLDWAIT set or has SIGCHLD set to
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* SIG_IGN, and the process has no unwaited-for children that were
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* transformed into zombie processes, the calling thread will block until all
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* of the children of the process containing the calling thread terminate, and
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* waitpid() will fail and set errno to ECHILD.
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*
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* If waitpid() returns because the status of a child process is available,
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* these functions will return a value equal to the process ID of the child
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* process. In this case, if the value of the argument stat_loc is not a
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* null pointer, information will be stored in the location pointed to by
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* stat_loc. The value stored at the location pointed to by stat_loc will be
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* 0 if and only if the status returned is from a terminated child process
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* that terminated by one of the following means:
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*
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* 1. The process returned 0 from main().
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* 2. The process called _exit() or exit() with a status argument of 0.
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* 3. The process was terminated because the last thread in the process terminated.
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*
|
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* Regardless of its value, this information may be interpreted using the
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* following macros, which are defined in <sys/wait.h> and evaluate to
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* integral expressions; the stat_val argument is the integer value pointed
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* to by stat_loc.
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*
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* WIFEXITED(stat_val) - Evaluates to a non-zero value if status was
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* returned for a child process that terminated normally.
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* WEXITSTATUS(stat_val) - If the value of WIFEXITED(stat_val) is non-zero,
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* this macro evaluates to the low-order 8 bits of the status argument
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* that the child process passed to _exit() or exit(), or the value the
|
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* child process returned from main().
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* WIFSIGNALED(stat_val) - Evaluates to a non-zero value if status was
|
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* returned for a child process that terminated due to the receipt of a
|
||||
* signal that was not caught (see <signal.h>).
|
||||
* WTERMSIG(stat_val) - If the value of WIFSIGNALED(stat_val) is non-zero,
|
||||
* this macro evaluates to the number of the signal that caused the
|
||||
* termination of the child process.
|
||||
* WIFSTOPPED(stat_val) - Evaluates to a non-zero value if status was
|
||||
* returned for a child process that is currently stopped.
|
||||
* WSTOPSIG(stat_val) - If the value of WIFSTOPPED(stat_val) is non-zero,
|
||||
* this macro evaluates to the number of the signal that caused the child
|
||||
* process to stop.
|
||||
* WIFCONTINUED(stat_val) - Evaluates to a non-zero value if status was
|
||||
* returned for a child process that has continued from a job control stop.
|
||||
*
|
||||
* Parameters:
|
||||
* pid - The task ID of the thread to waid for
|
||||
* stat_loc - The location to return the exit status
|
||||
* options - ignored
|
||||
*
|
||||
* Return Value:
|
||||
* If waitpid() returns because the status of a child process is available,
|
||||
* it will return a value equal to the process ID of the child process for
|
||||
* which status is reported.
|
||||
*
|
||||
* If waitpid() returns due to the delivery of a signal to the calling
|
||||
* process, -1 will be returned and errno set to EINTR.
|
||||
*
|
||||
* If waitpid() was invoked with WNOHANG set in options, it has at least
|
||||
* one child process specified by pid for which status is not available, and
|
||||
* status is not available for any process specified by pid, 0 is returned.
|
||||
*
|
||||
* Otherwise, (pid_t)-1 will be returned, and errno set to indicate the error:
|
||||
*
|
||||
* ECHILD - The process specified by pid does not exist or is not a child of
|
||||
* the calling process, or the process group specified by pid does not exist
|
||||
* or does not have any member process that is a child of the calling process.
|
||||
* EINTR - The function was interrupted by a signal. The value of the location
|
||||
* pointed to by stat_loc is undefined.
|
||||
* EINVAL - The options argument is not valid.
|
||||
*
|
||||
* Assumptions:
|
||||
*
|
||||
*****************************************************************************/
|
||||
|
||||
/***************************************************************************/
|
||||
/* NOTE: This is a partially functional, experimental version of waitpid() */
|
||||
/***************************************************************************/
|
||||
|
||||
pid_t waitpid(pid_t pid, int *stat_loc, int options)
|
||||
{
|
||||
_TCB *tcb = sched_gettcb(pid);
|
||||
bool mystat;
|
||||
int err;
|
||||
int ret;
|
||||
|
||||
/* Disable pre-emption so that nothing changes in the following tests */
|
||||
|
||||
sched_lock();
|
||||
if (!tcb)
|
||||
{
|
||||
err = ECHILD;
|
||||
goto errout_with_errno;
|
||||
}
|
||||
|
||||
/* None of the options are supported */
|
||||
|
||||
#ifdef CONFIG_DEBUG
|
||||
if (stat_loc == NULL)
|
||||
{
|
||||
err = EINVAL;
|
||||
goto errout_with_errno;
|
||||
}
|
||||
|
||||
if (options != 0)
|
||||
{
|
||||
err = ENOSYS;
|
||||
goto errout_with_errno;
|
||||
}
|
||||
#endif
|
||||
|
||||
/* "If more than one thread is suspended in waitpid() awaiting termination of
|
||||
* the same process, exactly one thread will return the process status at the
|
||||
* time of the target process termination." Hmmm.. what do we return to the
|
||||
* others?
|
||||
*/
|
||||
|
||||
if (tcb->stat_loc == NULL)
|
||||
{
|
||||
tcb->stat_loc = stat_loc;
|
||||
mystat = true;
|
||||
}
|
||||
|
||||
/* Then wait for the task to exit */
|
||||
|
||||
ret = sem_wait(&tcb->exitsem);
|
||||
if (ret < 0)
|
||||
{
|
||||
/* Unlock pre-emption and return the ERROR (sem_wait has already set
|
||||
* the errno). Handle the awkward case of whether or not we need to
|
||||
* nullify the stat_loc value.
|
||||
*/
|
||||
|
||||
if (mystat)
|
||||
{
|
||||
tcb->stat_loc = NULL;
|
||||
}
|
||||
goto errout;
|
||||
}
|
||||
|
||||
/* On success, return the PID */
|
||||
|
||||
sched_unlock();
|
||||
return pid;
|
||||
|
||||
errout_with_errno:
|
||||
errno = err;
|
||||
errout:
|
||||
sched_unlock();
|
||||
return ERROR;
|
||||
}
|
||||
|
||||
#endif /* CONFIG_SCHED_WAITPID */
|
||||
Loading…
Reference in New Issue