+++ /dev/null
-/* Support for an sbrk-like function that uses mmap. */
-
-/* Copyright (c) 2010-2022. The SimGrid Team.
- * All rights reserved. */
-
-/* This program is free software; you can redistribute it and/or modify it
- * under the terms of the license (GNU LGPL) which comes with this package. */
-
-/* Copyright 1992, 2000 Free Software Foundation, Inc.
-
- Contributed by Fred Fish at Cygnus Support. fnf@cygnus.com */
-
-#include <stdio.h>
-#include <fcntl.h>
-#include <sys/mman.h>
-#include <sys/wait.h>
-#include <errno.h>
-
-#include "mmprivate.h"
-
-#ifndef MAP_ANONYMOUS
-#define MAP_ANONYMOUS MAP_ANON
-#endif
-
-#define PAGE_ALIGN(addr) (void*)(((long)(addr) + mmalloc_pagesize - 1) & ~((long)mmalloc_pagesize - 1))
-
-/** @brief Add memory to this heap
- *
- * Get core for the memory region specified by MDP, using SIZE as the
- * amount to either add to or subtract from the existing region. Works
- * like sbrk(), but using mmap().
- *
- * It never returns NULL. Instead, it dies verbosely on errors.
- *
- * @param mdp The heap
- * @param size Bytes to allocate for this heap (or <0 to free memory from this heap)
- */
-void *mmorecore(struct mdesc *mdp, ssize_t size)
-{
- void* result; // please keep it uninitialized to track issues
- size_t mapbytes; /* Number of bytes to map */
- void* moveto; /* Address where we wish to move "break value" to */
- void* mapto; /* Address we actually mapped to */
-
- if (size == 0) {
- /* Just return the current "break" value. */
- return mdp->breakval;
- }
-
- if (mmalloc_pagesize == 0) { // Not initialized yet
- mmalloc_pagesize = (int)sysconf(_SC_PAGESIZE);
- }
-
- if (size < 0) {
- /* We are deallocating memory. If the amount requested would cause us to try to deallocate back past the base of
- * the mmap'd region then die verbosely. Otherwise, deallocate the memory and return the old break value. */
- if (((char*)mdp->breakval) + size >= (char*)mdp->base) {
- result = mdp->breakval;
- mdp->breakval = (char*)mdp->breakval + size;
- moveto = PAGE_ALIGN(mdp->breakval);
- munmap(moveto, (size_t)(((char*)mdp->top) - ((char*)moveto)) - 1);
- mdp->top = moveto;
- } else {
- fprintf(stderr,"Internal error: mmap was asked to deallocate more memory than it previously allocated. Bailling out now!\n");
- abort();
- }
- } else if ((char*)mdp->breakval + size > (char*)mdp->top) {
- /* The request would move us past the end of the currently mapped memory, so map in enough more memory to satisfy
- the request. This means we also have to grow the mapped-to file by an appropriate amount, since mmap cannot
- be used to extend a file. */
- moveto = PAGE_ALIGN((char*)mdp->breakval + size);
- mapbytes = (char*)moveto - (char*)mdp->top;
-
- /* Let's call mmap. Note that it is possible that mdp->top is 0. In this case mmap will choose the address for us.
- This call might very well overwrite an already existing memory mapping (leading to weird bugs).
- */
- mapto = mmap(mdp->top, mapbytes, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, -1, 0);
-
- if (mapto == MAP_FAILED) {
- char buff[1024];
- fprintf(stderr, "Internal error: mmap returned MAP_FAILED! pagesize:%d error: %s\n", mmalloc_pagesize,
- strerror(errno));
- snprintf(buff, 1024, "cat /proc/%d/maps", getpid());
- int status = system(buff);
- if (status == -1 || !(WIFEXITED(status) && WEXITSTATUS(status) == 0))
- fprintf(stderr, "Something went wrong when trying to %s\n", buff);
- sleep(1);
- abort();
- }
-
- if (mdp->top == 0)
- mdp->base = mdp->breakval = mapto;
-
- mdp->top = PAGE_ALIGN((char*)mdp->breakval + size);
- result = mdp->breakval;
- mdp->breakval = (char*)mdp->breakval + size;
- } else {
- /* Memory is already mapped, we only need to increase the breakval: */
- result = mdp->breakval;
- mdp->breakval = (char*)mdp->breakval + size;
- }
- return result;
-}