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Diffstat (limited to 'nuttx/lib/misc/lib_init.c')
-rw-r--r-- | nuttx/lib/misc/lib_init.c | 207 |
1 files changed, 207 insertions, 0 deletions
diff --git a/nuttx/lib/misc/lib_init.c b/nuttx/lib/misc/lib_init.c new file mode 100644 index 000000000..fb246b1ad --- /dev/null +++ b/nuttx/lib/misc/lib_init.c @@ -0,0 +1,207 @@ +/************************************************************ + * lib/misc/lib_init.c + * + * Copyright (C) 2007, 2011 Gregory Nutt. All rights reserved. + * Author: Gregory Nutt <spudmonkey@racsa.co.cr> + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 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. + * + ************************************************************/ + +/************************************************************ + * Included Files + ************************************************************/ + +#include <nuttx/config.h> + +#include <stdio.h> +#include <string.h> +#include <errno.h> + +#include <nuttx/kmalloc.h> +#include <nuttx/fs/fs.h> +#include <nuttx/lib.h> + +#include "lib_internal.h" + +/************************************************************ + * Definitions + ************************************************************/ + +/************************************************************ + * Private Variables + ************************************************************/ + +/************************************************************ + * Private Functions + ************************************************************/ + +/************************************************************ + * Public Functions + ************************************************************/ + +/************************************************************ + * lib_initialize + ************************************************************/ + +/* General library initialization hook */ + +void weak_const_function lib_initialize(void) +{ +} + +#if CONFIG_NFILE_STREAMS > 0 +/* The following function is called when a new TCB is allocated. It + * creates the streamlist instance that is stored in the TCB. + */ + +FAR struct streamlist *lib_alloclist(void) +{ + FAR struct streamlist *list; + list = (FAR struct streamlist*)lib_zalloc(sizeof(struct streamlist)); + if (list) + { + int i; + + /* Start with a reference count of one */ + + list->sl_crefs = 1; + + /* Initialize the list access mutex */ + + (void)sem_init(&list->sl_sem, 0, 1); + + /* Initialize each FILE structure */ + + for (i = 0; i < CONFIG_NFILE_STREAMS; i++) + { + /* Clear the IOB */ + + memset(&list->sl_streams[i], 0, sizeof(FILE)); + + /* Indicate not opened */ + + list->sl_streams[i].fs_filedes = -1; + + /* Initialize the stream semaphore to one to support one-at- + * a-time access to private data sets. + */ + + lib_sem_initialize(&list->sl_streams[i]); + } + } + return list; + +} + +/* This function is called when a TCB is closed (such as with + * pthread_create(). It increases the reference count on the stream + * list. + */ + +void lib_addreflist(FAR struct streamlist *list) +{ + if (list) + { + /* Increment the reference count on the list. + * NOTE: that we disable interrupts to do this + * (vs. taking the list semaphore). We do this + * because file cleanup operations often must be + * done from the IDLE task which cannot wait + * on semaphores. + */ + + register irqstate_t flags = irqsave(); + list->sl_crefs++; + irqrestore(flags); + } +} + +/* this function is called when a TCB is destroyed. Note that is + * does not close the file by release this inode. This happens + * separately when the file descriptor list is freed. + */ + +void lib_releaselist(FAR struct streamlist *list) +{ + int crefs; + if (list) + { + /* Decrement the reference count on the list. + * NOTE: that we disable interrupts to do this + * (vs. taking the list semaphore). We do this + * because file cleanup operations often must be + * done from the IDLE task which cannot wait + * on semaphores. + */ + + register irqstate_t flags = irqsave(); + crefs = --(list->sl_crefs); + irqrestore(flags); + + /* If the count decrements to zero, then there is no reference + * to the structure and it should be deallocated. Since there + * are references, it would be an error if any task still held + * a reference to the list's semaphore. + */ + + if (crefs <= 0) + { +#if CONFIG_STDIO_BUFFER_SIZE > 0 + int i; +#endif + /* Destroy the semaphore and release the filelist */ + + (void)sem_destroy(&list->sl_sem); + + /* Release each stream in the list */ + +#if CONFIG_STDIO_BUFFER_SIZE > 0 + for (i = 0; i < CONFIG_NFILE_STREAMS; i++) + { + /* Destroy the semaphore that protects the IO buffer */ + + (void)sem_destroy(&list->sl_streams[i].fs_sem); + + /* Release the IO buffer */ + if (list->sl_streams[i].fs_bufstart) + { + sched_free(list->sl_streams[i].fs_bufstart); + } + } +#endif + /* Finally, release the list itself */ + + sched_free(list); + } + } +} + +#endif /* CONFIG_NFILE_STREAMS */ + + |