Files
threadx/utility/rtos_compatibility_layers/posix/px_mq_find_queue.c
2021-07-28 07:24:02 +00:00

114 lines
5.8 KiB
C

/**************************************************************************/
/* */
/* Copyright (c) Microsoft Corporation. All rights reserved. */
/* */
/* This software is licensed under the Microsoft Software License */
/* Terms for Microsoft Azure RTOS. Full text of the license can be */
/* found in the LICENSE file at https://aka.ms/AzureRTOS_EULA */
/* and in the root directory of this software. */
/* */
/**************************************************************************/
/**************************************************************************/
/**************************************************************************/
/** */
/** POSIX wrapper for THREADX */
/** */
/** */
/** */
/**************************************************************************/
/**************************************************************************/
/* Include necessary system files. */
#include "tx_api.h" /* Threadx API */
#include "pthread.h" /* Posix API */
#include "px_int.h" /* Posix helper functions */
/**************************************************************************/
/* */
/* FUNCTION RELEASE */
/* */
/* posix_find_queue PORTABLE C */
/* 6.1.7 */
/* AUTHOR */
/* */
/* William E. Lamie, Microsoft Corporation */
/* */
/* DESCRIPTION */
/* */
/* This routine returns queue descriptor indicating that name of */
/* in the message queue.exists. */
/* */
/* INPUT */
/* */
/* const char * mq_name Name of the message queue */
/* */
/* OUTPUT */
/* */
/* q_ptr If successful */
/* */
/* CALLS */
/* */
/* None */
/* */
/* CALLED BY */
/* */
/* POSIX internal Code */
/* */
/* RELEASE HISTORY */
/* */
/* DATE NAME DESCRIPTION */
/* */
/* 06-02-2021 William E. Lamie Initial Version 6.1.7 */
/* */
/**************************************************************************/
POSIX_MSG_QUEUE * posix_find_queue(const CHAR *mq_name)
{
POSIX_MSG_QUEUE *q_ptr;
ULONG index;
ULONG match;
CHAR *dummy_name;
CHAR *dummy_queue_name;
ULONG namelength;
q_ptr = (POSIX_MSG_QUEUE*)NULL;
/* For checking the name. */
for(index = 0,q_ptr = posix_queue_pool;index < POSIX_MAX_QUEUES ;index ++,q_ptr ++)
{
/* Assume the worst case. */
match = TX_FALSE;
if(q_ptr->in_use == TX_TRUE)
{
dummy_queue_name = q_ptr->name;
for(namelength = 0 ,dummy_name = (CHAR *) mq_name ; namelength < PATH_MAX ;
namelength ++, dummy_name++,dummy_queue_name ++)
{
/* Copy name. */
if (*dummy_name == *dummy_queue_name)
{
/* End of the string. */
if(*dummy_name == '\0')
{
match = TX_TRUE;
break;
}
}/* Copy name. */
else
break;
}
}
if(match==TX_TRUE)
break;
}
/* For each message queue. */
if(match==TX_TRUE)
return(q_ptr);
/* Returns NULL if match not found. */
q_ptr = (POSIX_MSG_QUEUE*)NULL;
return (q_ptr);
}