/*
* Copyright (c) 2013 Jiri Zarevucky
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - 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.
* - The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*/
/** @addtogroup libc
* @{
*/
/**
* @file
* @brief
*/
#include <vfs/inbox.h>
#include <vfs/vfs.h>
#include <adt/list.h>
#include <str.h>
#include <stdlib.h>
#include <loader/pcb.h>
#include "../private/io.h"
#include <errno.h>
/*
* This is an attempt at generalization of the "standard files" concept to
* arbitrary names. When loading a task, the parent can put arbitrary files to
* an "inbox" through IPC calls, every file in an inbox has a name assigned
* (e.g. "stdin", "stdout", "stderr", "data", "logfile", etc.). The client then
* retrieves those files from inbox by name. "stdin", "stdout" and "stderr" are
* handled automatically by libc to initialize standard <stdio.h> streams and
* legacy file descriptors 0, 1, 2. Other names are subject to conventions and
* application-specific rules.
*/
typedef struct {
link_t link;
char *name;
int file;
} inbox_entry;
static LIST_INITIALIZE(inb_list);
/** Inserts a named file into the inbox.
*
* If a file with the same name is already present, it overwrites it and returns
* the original value. Otherwise, it returns -1. If the argument 'file' is -1,
* nothing is inserted and the file with specified name is removed and returned
* if present.
*
* @param name Name of the inbox entry.
* @param file File to insert or -1.
* @return Original value of the entry or -1 if not originally present.
*/
int inbox_set(const char *name, int file)
{
inbox_entry *next = NULL;
int result;
list_foreach(inb_list, link, inbox_entry, e) {
int cmp = str_cmp(e->name, name);
switch (cmp) {
case -1:
continue;
case 0:
result = e->file;
if (file == -1) {
free(e->name);
/* Safe because we exit immediately. */
list_remove(&e->link);
} else {
e->file = file;
}
return result;
case 1:
next = e;
goto out;
}
}
out:
if (file == -1)
return -1;
inbox_entry *entry = calloc(sizeof(inbox_entry), 1);
entry->name = str_dup(name);
entry->file = file;
if (next == NULL) {
list_append((link_t *)entry, &inb_list);
} else {
list_insert_before((link_t *)entry, (link_t *)next);
}
return -1;
}
/** Retrieve a file with this name.
*
* @param name Name of the entry.
* @return Requested file or -1 if not set.
*/
int inbox_get(const char *name)
{
list_foreach(inb_list, link, inbox_entry, e) {
int cmp = str_cmp(e->name, name);
switch (cmp) {
case 0:
return e->file;
case 1:
return -1;
}
}
return -1;
}
/** Writes names of entries that are currently set into an array provided by the
* user.
*
* @param names Array in which names are stored.
* @param capacity Capacity of the array.
* @return Number of entries written. If capacity == 0, return the total number
* of entries.
*/
int inbox_list(const char **names, int capacity)
{
if (capacity == 0)
return list_count(&inb_list);
int used = 0;
list_foreach(inb_list, link, inbox_entry, e) {
if (used == capacity)
return used;
names[used] = e->name;
used++;
}
return used;
}
void __inbox_init(struct pcb_inbox_entry *entries, int count)
{
for (int i = 0; i < count; i++) {
int original = inbox_set(entries[i].name, entries[i].file);
if (original >= 0)
vfs_put(original);
}
}
/**
* @}
*/