components/newlib/reent_init.c (ESP-IDF)

/* * SPDX-FileCopyrightText: 2015-2023 Espressif Systems (Shanghai) CO LTD * * SPDX-License-Identifier: Apache-2.0 */ #include <string.h> #include <stdbool.h> #include <stdlib.h> #include <stdio.h> #include <sys/reent.h> #include "esp_attr.h" /** * This is the replacement for newlib's _REENT_INIT_PTR and __sinit. * The problem with __sinit is that it allocates three FILE structures * (stdin, stdout, stderr). Having individual standard streams for each task * is a bit too much on a small embedded system. So we point streams * to the streams of the global struct _reent, which are initialized in * startup code. */ void IRAM_ATTR esp_reent_init(struct _reent* r) { memset(r, 0, sizeof(*r)); _REENT_STDIN(r) = _REENT_STDIN(_GLOBAL_REENT); _REENT_STDOUT(r) = _REENT_STDOUT(_GLOBAL_REENT); _REENT_STDERR(r) = _REENT_STDERR(_GLOBAL_REENT); _REENT_CLEANUP(r) = _REENT_CLEANUP(_GLOBAL_REENT); _REENT_SDIDINIT(r) = _REENT_SDIDINIT(_GLOBAL_REENT); } /* only declared in private stdio header file, local.h */ extern void __sfp_lock_acquire(void); extern void __sfp_lock_release(void); void esp_reent_cleanup(void) { struct _reent* r = __getreent(); _reclaim_reent(r); r->_emergency = NULL; r->_mp = NULL; r->_r48 = NULL; r->_localtime_buf = NULL; r->_asctime_buf = NULL; r->_signal_buf = NULL; r->_misc = NULL; r->_cvtbuf = NULL; /* Clean up "glue" (lazily-allocated FILE objects) */ struct _glue* prev = &_REENT_SGLUE(_GLOBAL_REENT); for (struct _glue * cur = _REENT_SGLUE(_GLOBAL_REENT)._next; cur != NULL;) { if (cur->_niobs == 0) { cur = cur->_next; continue; } bool has_open_files = false; for (int i = 0; i < cur->_niobs; ++i) { FILE* fp = &cur->_iobs[i]; if (fp->_flags != 0) { has_open_files = true; break; } } if (has_open_files) { prev = cur; cur = cur->_next; continue; } struct _glue * next = cur->_next; prev->_next = next; free(cur); cur = next; } }