Initial creation of sourceware repositorygdb-4_18-branchpoint

1 files changed, 337 insertions, 0 deletions

diff --git a/mmalloc/mmalloc.c b/mmalloc/mmalloc.c
new file mode 100644
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--- /dev/null
+++ b/mmalloc/mmalloc.c
@@ -0,0 +1,337 @@
+/* Memory allocator `malloc'.
+   Copyright 1990, 1991, 1992 Free Software Foundation
+
+   Written May 1989 by Mike Haertel.
+   Heavily modified Mar 1992 by Fred Fish for mmap'd version.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+
+The GNU C Library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA.
+
+   The author may be reached (Email) at the address mike@ai.mit.edu,
+   or (US mail) as Mike Haertel c/o Free Software Foundation. */
+
+#include <string.h>	/* Prototypes for memcpy, memmove, memset, etc */
+
+#include "mmprivate.h"
+
+/* Prototypes for local functions */
+
+static int initialize PARAMS ((struct mdesc *));
+static PTR morecore PARAMS ((struct mdesc *, size_t));
+static PTR align PARAMS ((struct mdesc *, size_t));
+
+/* Aligned allocation.  */
+
+static PTR
+align (mdp, size)
+  struct mdesc *mdp;
+  size_t size;
+{
+  PTR result;
+  unsigned long int adj;
+
+  result = mdp -> morecore (mdp, size);
+  adj = RESIDUAL (result, BLOCKSIZE);
+  if (adj != 0)
+    {
+      adj = BLOCKSIZE - adj;
+      mdp -> morecore (mdp, adj);
+      result = (char *) result + adj;
+    }
+  return (result);
+}
+
+/* Set everything up and remember that we have.  */
+
+static int
+initialize (mdp)
+  struct mdesc *mdp;
+{
+  mdp -> heapsize = HEAP / BLOCKSIZE;
+  mdp -> heapinfo = (malloc_info *) 
+    align (mdp, mdp -> heapsize * sizeof (malloc_info));
+  if (mdp -> heapinfo == NULL)
+    {
+      return (0);
+    }
+  memset ((PTR)mdp -> heapinfo, 0, mdp -> heapsize * sizeof (malloc_info));
+  mdp -> heapinfo[0].free.size = 0;
+  mdp -> heapinfo[0].free.next = mdp -> heapinfo[0].free.prev = 0;
+  mdp -> heapindex = 0;
+  mdp -> heapbase = (char *) mdp -> heapinfo;
+  mdp -> flags |= MMALLOC_INITIALIZED;
+  return (1);
+}
+
+/* Get neatly aligned memory, initializing or
+   growing the heap info table as necessary. */
+
+static PTR
+morecore (mdp, size)
+  struct mdesc *mdp;
+  size_t size;
+{
+  PTR result;
+  malloc_info *newinfo, *oldinfo;
+  size_t newsize;
+
+  result = align (mdp, size);
+  if (result == NULL)
+    {
+      return (NULL);
+    }
+
+  /* Check if we need to grow the info table.  */
+  if ((size_t) BLOCK ((char *) result + size) > mdp -> heapsize)
+    {
+      newsize = mdp -> heapsize;
+      while ((size_t) BLOCK ((char *) result + size) > newsize)
+	{
+	  newsize *= 2;
+	}
+      newinfo = (malloc_info *) align (mdp, newsize * sizeof (malloc_info));
+      if (newinfo == NULL)
+	{
+	  mdp -> morecore (mdp, -size);
+	  return (NULL);
+	}
+      memset ((PTR) newinfo, 0, newsize * sizeof (malloc_info));
+      memcpy ((PTR) newinfo, (PTR) mdp -> heapinfo,
+	      mdp -> heapsize * sizeof (malloc_info));
+      oldinfo = mdp -> heapinfo;
+      newinfo[BLOCK (oldinfo)].busy.type = 0;
+      newinfo[BLOCK (oldinfo)].busy.info.size
+	= BLOCKIFY (mdp -> heapsize * sizeof (malloc_info));
+      mdp -> heapinfo = newinfo;
+      __mmalloc_free (mdp, (PTR)oldinfo);
+      mdp -> heapsize = newsize;
+    }
+
+  mdp -> heaplimit = BLOCK ((char *) result + size);
+  return (result);
+}
+
+/* Allocate memory from the heap.  */
+
+PTR
+mmalloc (md, size)
+  PTR md;
+  size_t size;
+{
+  struct mdesc *mdp;
+  PTR result;
+  size_t block, blocks, lastblocks, start;
+  register size_t i;
+  struct list *next;
+  register size_t log;
+
+  if (size == 0)
+    {
+      return (NULL);
+    }
+
+  mdp = MD_TO_MDP (md);
+      
+  if (mdp -> mmalloc_hook != NULL)
+    {
+      return ((*mdp -> mmalloc_hook) (md, size));
+    }
+
+  if (!(mdp -> flags & MMALLOC_INITIALIZED))
+    {
+      if (!initialize (mdp))
+	{
+	  return (NULL);
+	}
+    }
+
+  if (size < sizeof (struct list))
+    {
+      size = sizeof (struct list);
+    }
+
+  /* Determine the allocation policy based on the request size.  */
+  if (size <= BLOCKSIZE / 2)
+    {
+      /* Small allocation to receive a fragment of a block.
+	 Determine the logarithm to base two of the fragment size. */
+      log = 1;
+      --size;
+      while ((size /= 2) != 0)
+	{
+	  ++log;
+	}
+
+      /* Look in the fragment lists for a
+	 free fragment of the desired size. */
+      next = mdp -> fraghead[log].next;
+      if (next != NULL)
+	{
+	  /* There are free fragments of this size.
+	     Pop a fragment out of the fragment list and return it.
+	     Update the block's nfree and first counters. */
+	  result = (PTR) next;
+	  next -> prev -> next = next -> next;
+	  if (next -> next != NULL)
+	    {
+	      next -> next -> prev = next -> prev;
+	    }
+	  block = BLOCK (result);
+	  if (--mdp -> heapinfo[block].busy.info.frag.nfree != 0)
+	    {
+	      mdp -> heapinfo[block].busy.info.frag.first =
+		RESIDUAL (next -> next, BLOCKSIZE) >> log;
+	    }
+
+	  /* Update the statistics.  */
+	  mdp -> heapstats.chunks_used++;
+	  mdp -> heapstats.bytes_used += 1 << log;
+	  mdp -> heapstats.chunks_free--;
+	  mdp -> heapstats.bytes_free -= 1 << log;
+	}
+      else
+	{
+	  /* No free fragments of the desired size, so get a new block
+	     and break it into fragments, returning the first.  */
+	  result = mmalloc (md, BLOCKSIZE);
+	  if (result == NULL)
+	    {
+	      return (NULL);
+	    }
+
+	  /* Link all fragments but the first into the free list.  */
+	  for (i = 1; i < (size_t) (BLOCKSIZE >> log); ++i)
+	    {
+	      next = (struct list *) ((char *) result + (i << log));
+	      next -> next = mdp -> fraghead[log].next;
+	      next -> prev = &mdp -> fraghead[log];
+	      next -> prev -> next = next;
+	      if (next -> next != NULL)
+		{
+		  next -> next -> prev = next;
+		}
+	    }
+
+	  /* Initialize the nfree and first counters for this block.  */
+	  block = BLOCK (result);
+	  mdp -> heapinfo[block].busy.type = log;
+	  mdp -> heapinfo[block].busy.info.frag.nfree = i - 1;
+	  mdp -> heapinfo[block].busy.info.frag.first = i - 1;
+
+	  mdp -> heapstats.chunks_free += (BLOCKSIZE >> log) - 1;
+	  mdp -> heapstats.bytes_free += BLOCKSIZE - (1 << log);
+ 	  mdp -> heapstats.bytes_used -= BLOCKSIZE - (1 << log);
+	}
+    }
+  else
+    {
+      /* Large allocation to receive one or more blocks.
+	 Search the free list in a circle starting at the last place visited.
+	 If we loop completely around without finding a large enough
+	 space we will have to get more memory from the system.  */
+      blocks = BLOCKIFY(size);
+      start = block = MALLOC_SEARCH_START;
+      while (mdp -> heapinfo[block].free.size < blocks)
+	{
+	  block = mdp -> heapinfo[block].free.next;
+	  if (block == start)
+	    {
+	      /* Need to get more from the system.  Check to see if
+		 the new core will be contiguous with the final free
+		 block; if so we don't need to get as much.  */
+	      block = mdp -> heapinfo[0].free.prev;
+	      lastblocks = mdp -> heapinfo[block].free.size;
+	      if (mdp -> heaplimit != 0 &&
+		  block + lastblocks == mdp -> heaplimit &&
+		  mdp -> morecore (mdp, 0) == ADDRESS(block + lastblocks) &&
+		  (morecore (mdp, (blocks - lastblocks) * BLOCKSIZE)) != NULL)
+		{
+		  /* Which block we are extending (the `final free
+		     block' referred to above) might have changed, if
+		     it got combined with a freed info table.  */
+		  block = mdp -> heapinfo[0].free.prev;
+
+		  mdp -> heapinfo[block].free.size += (blocks - lastblocks);
+		  mdp -> heapstats.bytes_free +=
+		      (blocks - lastblocks) * BLOCKSIZE;
+		  continue;
+		}
+	      result = morecore(mdp, blocks * BLOCKSIZE);
+	      if (result == NULL)
+		{
+		  return (NULL);
+		}
+	      block = BLOCK (result);
+	      mdp -> heapinfo[block].busy.type = 0;
+	      mdp -> heapinfo[block].busy.info.size = blocks;
+	      mdp -> heapstats.chunks_used++;
+	      mdp -> heapstats.bytes_used += blocks * BLOCKSIZE;
+	      return (result);
+	    }
+	}
+
+      /* At this point we have found a suitable free list entry.
+	 Figure out how to remove what we need from the list. */
+      result = ADDRESS(block);
+      if (mdp -> heapinfo[block].free.size > blocks)
+	{
+	  /* The block we found has a bit left over,
+	     so relink the tail end back into the free list. */
+	  mdp -> heapinfo[block + blocks].free.size
+	    = mdp -> heapinfo[block].free.size - blocks;
+	  mdp -> heapinfo[block + blocks].free.next
+	    = mdp -> heapinfo[block].free.next;
+	  mdp -> heapinfo[block + blocks].free.prev
+	    = mdp -> heapinfo[block].free.prev;
+	  mdp -> heapinfo[mdp -> heapinfo[block].free.prev].free.next
+	    = mdp -> heapinfo[mdp -> heapinfo[block].free.next].free.prev
+	      = mdp -> heapindex = block + blocks;
+	}
+      else
+	{
+	  /* The block exactly matches our requirements,
+	     so just remove it from the list. */
+	  mdp -> heapinfo[mdp -> heapinfo[block].free.next].free.prev
+	    = mdp -> heapinfo[block].free.prev;
+	  mdp -> heapinfo[mdp -> heapinfo[block].free.prev].free.next
+	    = mdp -> heapindex = mdp -> heapinfo[block].free.next;
+	  mdp -> heapstats.chunks_free--;
+	}
+
+      mdp -> heapinfo[block].busy.type = 0;
+      mdp -> heapinfo[block].busy.info.size = blocks;
+      mdp -> heapstats.chunks_used++;
+      mdp -> heapstats.bytes_used += blocks * BLOCKSIZE;
+      mdp -> heapstats.bytes_free -= blocks * BLOCKSIZE;
+    }
+
+  return (result);
+}
+
+/* When using this package, provide a version of malloc/realloc/free built
+   on top of it, so that if we use the default sbrk() region we will not
+   collide with another malloc package trying to do the same thing, if
+   the application contains any "hidden" calls to malloc/realloc/free (such
+   as inside a system library). */
+
+PTR
+malloc (size)
+  size_t size;
+{
+  PTR result;
+
+  result = mmalloc ((PTR) NULL, size);
+  return (result);
+}