1.1 --- a/libc/Makefile	Wed Oct 16 00:52:26 2019 +0200
     1.2 +++ b/libc/Makefile	Fri Oct 18 01:05:43 2019 +0200
     1.3 @@ -57,7 +57,9 @@
     1.4  
     1.5  # System integration sources.
     1.6  
     1.7 -SOURCES_SYSTEM	= l4re/syscalls.c l4re/sys_client.c
     1.8 +SOURCES_SYSTEM	= $(wildcard $(THISDIR)/l4re/*.c)
     1.9 +
    1.10 +SOURCES_SYSTEM_RELATIVE = $(patsubst $(THISDIR)/%,%,$(SOURCES_SYSTEM))
    1.11  
    1.12  # Some stdio files are generated from the same file using different definitions.
    1.13  # See the rules at the end for the generation of these files.
    1.14 @@ -112,7 +114,7 @@
    1.15  # generated files, plus the required libm files.
    1.16  
    1.17  SRC_C		= \
    1.18 -		$(SOURCES_SYSTEM) \
    1.19 +		$(SOURCES_SYSTEM_RELATIVE) \
    1.20  		$(filter-out \
    1.21  			$(SOURCES_DISABLED) \
    1.22  			$(SOURCES_DISCARDED), \

     2.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     2.2 +++ b/libc/l4re/sys_memory.c	Fri Oct 18 01:05:43 2019 +0200
     2.3 @@ -0,0 +1,115 @@
     2.4 +/*
     2.5 + * Traditional system functions for memory management.
     2.6 + *
     2.7 + * Copyright (C) 2019 Paul Boddie <paul@boddie.org.uk>
     2.8 + *
     2.9 + * This program is free software; you can redistribute it and/or
    2.10 + * modify it under the terms of the GNU General Public License as
    2.11 + * published by the Free Software Foundation; either version 2 of
    2.12 + * the License, or (at your option) any later version.
    2.13 + *
    2.14 + * This program is distributed in the hope that it will be useful,
    2.15 + * but WITHOUT ANY WARRANTY; without even the implied warranty of
    2.16 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    2.17 + * GNU General Public License for more details.
    2.18 + *
    2.19 + * You should have received a copy of the GNU General Public License
    2.20 + * along with this program; if not, write to the Free Software
    2.21 + * Foundation, Inc., 51 Franklin Street, Fifth Floor,
    2.22 + * Boston, MA  02110-1301, USA
    2.23 + */
    2.24 +
    2.25 +#include <l4/sys/types.h>
    2.26 +
    2.27 +#include <stdlib.h>
    2.28 +
    2.29 +#include <ipc/mem_ipc.h>
    2.30 +
    2.31 +#include "sys_memory.h"
    2.32 +
    2.33 +
    2.34 +
    2.35 +/* NOTE: This should use the reentrancy state and prevent concurrent access. */
    2.36 +
    2.37 +/* The current and previous limit of the data segment. */
    2.38 +
    2.39 +static void *program_break = 0;
    2.40 +static void *program_break_previous = 0;
    2.41 +
    2.42 +/* Available memory already allocated. */
    2.43 +
    2.44 +const unsigned long initial_memory_size = L4_PAGESIZE;
    2.45 +unsigned long memory_available = 0;
    2.46 +
    2.47 +
    2.48 +
    2.49 +/* Return the "program break" or address of the first location after the end of
    2.50 +   the data segment. If increment is non-zero, allocate more data space and
    2.51 +   provide the address before allocation as the result. */
    2.52 +
    2.53 +void *sys_sbrk(intptr_t increment)
    2.54 +{
    2.55 +  l4_cap_idx_t ds;
    2.56 +  void *addr;
    2.57 +  unsigned long size, requested;
    2.58 +
    2.59 +  /* For a zero increment, obtain the current limit. */
    2.60 +
    2.61 +  if (!increment)
    2.62 +  {
    2.63 +    /* Without any recorded address, obtain some memory first in order to provide
    2.64 +       the initial address. */
    2.65 +
    2.66 +    if (!program_break)
    2.67 +    {
    2.68 +      if (ipc_allocate(initial_memory_size, &program_break_previous, &ds))
    2.69 +        return (void *) -1;
    2.70 +
    2.71 +      if (ipc_dataspace_size(ds, &memory_available))
    2.72 +        return (void *) -1;
    2.73 +
    2.74 +      /* The actual limit is concealed from the caller. */
    2.75 +
    2.76 +      program_break = program_break_previous;
    2.77 +    }
    2.78 +  }
    2.79 +
    2.80 +  /* For a non-zero increment, obtain a new limit, using any available memory
    2.81 +     from initialisation. */
    2.82 +
    2.83 +  /* NOTE: For now, ignore negative increments. */
    2.84 +
    2.85 +  else if (increment > 0)
    2.86 +  {
    2.87 +    program_break_previous = program_break;
    2.88 +
    2.89 +    /* Consume available pre-allocated memory if possible. */
    2.90 +
    2.91 +    requested = labs(increment);
    2.92 +
    2.93 +    if (memory_available >= requested)
    2.94 +    {
    2.95 +      memory_available -= requested;
    2.96 +      program_break += requested;
    2.97 +    }
    2.98 +
    2.99 +    /* Without any available pre-allocated memory, obtain a new dataspace and
   2.100 +       advance the address. */
   2.101 +
   2.102 +    else
   2.103 +    {
   2.104 +      if (ipc_allocate(requested - memory_available, &addr, &ds))
   2.105 +        return (void *) -1;
   2.106 +
   2.107 +      if (ipc_dataspace_size(ds, &size))
   2.108 +        return (void *) -1;
   2.109 +
   2.110 +      program_break += size;
   2.111 +      memory_available = 0;
   2.112 +    }
   2.113 +  }
   2.114 +
   2.115 +  /* Return the previous limit. */
   2.116 +
   2.117 +  return program_break_previous;
   2.118 +}

     3.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     3.2 +++ b/libc/l4re/sys_memory.h	Fri Oct 18 01:05:43 2019 +0200
     3.3 @@ -0,0 +1,26 @@
     3.4 +/*
     3.5 + * Traditional system functions for memory management.
     3.6 + *
     3.7 + * Copyright (C) 2019 Paul Boddie <paul@boddie.org.uk>
     3.8 + *
     3.9 + * This program is free software; you can redistribute it and/or
    3.10 + * modify it under the terms of the GNU General Public License as
    3.11 + * published by the Free Software Foundation; either version 2 of
    3.12 + * the License, or (at your option) any later version.
    3.13 + *
    3.14 + * This program is distributed in the hope that it will be useful,
    3.15 + * but WITHOUT ANY WARRANTY; without even the implied warranty of
    3.16 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    3.17 + * GNU General Public License for more details.
    3.18 + *
    3.19 + * You should have received a copy of the GNU General Public License
    3.20 + * along with this program; if not, write to the Free Software
    3.21 + * Foundation, Inc., 51 Franklin Street, Fifth Floor,
    3.22 + * Boston, MA  02110-1301, USA
    3.23 + */
    3.24 +
    3.25 +#pragma once
    3.26 +
    3.27 +#include <unistd.h>
    3.28 +
    3.29 +void *sys_sbrk(intptr_t increment);

     4.1 --- a/libc/l4re/syscalls.c	Wed Oct 16 00:52:26 2019 +0200
     4.2 +++ b/libc/l4re/syscalls.c	Fri Oct 18 01:05:43 2019 +0200
     4.3 @@ -30,7 +30,8 @@
     4.4  
     4.5  #include <reent.h>            /* struct _reent */
     4.6  
     4.7 -#include "sys_client.h"
     4.8 +#include "sys_client.h"       /* close, open, read, write */
     4.9 +#include "sys_memory.h"       /* sbrk */
    4.10  
    4.11  int _close_r(struct _reent *reent, int fd)
    4.12  {
    4.13 @@ -121,7 +122,8 @@
    4.14  
    4.15  void *_sbrk_r(struct _reent *reent, intptr_t increment)
    4.16  {
    4.17 -  return (void *) -1;
    4.18 +  /* NOTE: Not handling errno yet. */
    4.19 +  return sys_sbrk(increment);
    4.20  }
    4.21  
    4.22  int _stat_r(struct _reent *reent, const char *pathname, struct stat *buf)