/*

  Copyright (C) 2000,2002,2004 Silicon Graphics, Inc.  All Rights Reserved.

  Portions Copyright (C) 2007 David Anderson. All Rights Reserved.

  This program is free software; you can redistribute it and/or modify it

  under the terms of version 2.1 of the GNU Lesser General Public License 

  as published by the Free Software Foundation.

  This program is distributed in the hope that it would be useful, but

  WITHOUT ANY WARRANTY; without even the implied warranty of

  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  

  Further, this software is distributed without any warranty that it is

  free of the rightful claim of any third person regarding infringement 

  or the like.  Any license provided herein, whether implied or 

  otherwise, applies only to this software file.  Patent licenses, if

  any, provided herein do not apply to combinations of this program with 

  other software, or any other product whatsoever.  

  You should have received a copy of the GNU Lesser General Public 

  License along with this program; if not, write the Free Software 

  Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston MA 02110-1301,

  USA.

  Contact information:  Silicon Graphics, Inc., 1500 Crittenden Lane,

  Mountain View, CA 94043, or:

  http://www.sgi.com

  For further information regarding this notice, see:

  http://oss.sgi.com/projects/GenInfo/NoticeExplan

*/

/* The address of the Free Software Foundation is

   Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, 

   Boston, MA 02110-1301, USA.

   SGI has moved from the Crittenden Lane address.

*/

#include "config.h"

#include "dwarf_incl.h"

#include <stdio.h>

#include <limits.h>

#ifdef HAVE_STDLIB_H

#include <stdlib.h>

#endif /* HAVE_STDLIB_H */

#include "dwarf_macro.h"

#define LEFTPAREN '('

#define RIGHTPAREN ')'

#define SPACE ' '

/*

	Given the dwarf macro string, return a pointer to

	the value.  Returns pointer to 0 byte at end of string

	if no value found (meaning the value is the empty string).

	Only understands well-formed dwarf macinfo strings.

*/

char *

dwarf_find_macro_value_start(char *str)

{

    char *lcp;

    int funclike = 0;

    for (lcp = str; *lcp; ++lcp) {

	switch (*lcp) {

	case LEFTPAREN:

	    funclike = 1;

	    break;

	case RIGHTPAREN:

	    /* lcp+1 must be a space, and following char is the value */

	    return lcp + 2;

	case SPACE:

	    /* we allow extraneous spaces inside macro parameter **

	       list, just in case... This is not really needed. */

	    if (!funclike) {

		return lcp + 1;

	    }

	    break;

	}

    }

    /* never found value: returns pointer to the 0 byte at end of

       string */

    return lcp;

}

/*

   Try to keep fileindex correct in every Macro_Details

   record by tracking file starts and ends.

   Uses high water mark: space reused, not freed.

   Presumption is that this makes sense for most uses.

   STARTERMAX is set so that the array need not be expanded for

   most files: it is the initial include file depth.

*/

struct macro_stack_s {

    Dwarf_Signed *st_base;

    long max;

    long next_to_use;

    int was_fault;

};

static void _dwarf_reset_index_macro_stack(struct macro_stack_s *ms);

static void

free_macro_stack(Dwarf_Debug dbg, struct macro_stack_s *ms)

{

    dwarf_dealloc(dbg,ms->st_base,DW_DLA_STRING);

    _dwarf_reset_index_macro_stack(ms);

}

#define STARTERMAX 10

static void

_dwarf_reset_index_macro_stack(struct macro_stack_s *ms)

{

    ms->st_base = 0;

    ms->max = 0;

    ms->next_to_use = 0;

    ms->was_fault = 0;

}

static int

_dwarf_macro_stack_push_index(Dwarf_Debug dbg, Dwarf_Signed indx,

			      struct macro_stack_s *ms)

{

    Dwarf_Signed *newbase;

    if (ms->next_to_use >= ms->max) {

	long new_size;

	if (ms->max == 0) {

	    ms->max = STARTERMAX;

	}

	new_size = ms->max * 2;

	newbase =

	    _dwarf_get_alloc(dbg, DW_DLA_STRING,

			     new_size * sizeof(Dwarf_Signed));

	if (newbase == 0) {

	    /* just leave the old array in place */

	    ms->was_fault = 1;

	    return DW_DLV_ERROR;

	}

        if(ms->st_base) {

	    memcpy(newbase, ms->st_base,

	       ms->next_to_use * sizeof(Dwarf_Signed));

	    dwarf_dealloc(dbg, ms->st_base, DW_DLA_STRING);

        }

	ms->st_base = newbase;

	ms->max = new_size;

    }

    ms->st_base[ms->next_to_use] = indx;

    ++ms->next_to_use;

    return DW_DLV_OK;

}

static Dwarf_Signed

_dwarf_macro_stack_pop_index(struct macro_stack_s *ms)

{

    if (ms->was_fault) {

	return -1;

    }

    if (ms->next_to_use > 0) {

	ms->next_to_use--;

	return (ms->st_base[ms->next_to_use]);

    } else {

        ms->was_fault = 1;

    }

    return -1;

}

/* starting at macro_offset in .debug_macinfo,

	if maximum_count is 0, treat as if it is infinite.

	get macro data up thru

	maximum_count entries or the end of a compilation

	unit's entries (whichever comes first). 

*/

int

dwarf_get_macro_details(Dwarf_Debug dbg,

			Dwarf_Off macro_offset,

			Dwarf_Unsigned maximum_count,

			Dwarf_Signed * entry_count,

			Dwarf_Macro_Details ** details,

			Dwarf_Error * error)

{

    Dwarf_Small *macro_base = 0;

    Dwarf_Small *pnext = 0;

    Dwarf_Unsigned endloc = 0;

    unsigned char uc = 0;

    unsigned long depth = 0;	/* By section 6.3.2 Dwarf3 draft 8/9,

				   the base file should appear as

				   DW_MACINFO_start_file. See

				   http://gcc.gnu.org/ml/gcc-bugs/2005-02/msg03442.html

				   on "[Bug debug/20253] New: [3.4/4.0 regression]:

				   Macro debug info broken due to lexer change" for how

				   gcc is broken in some versions. We no longer use

				   depth as a stopping point, it's not needed as a

				   stopping point anyway.  */

    int res = 0;

    /* count space used by strings */

    unsigned long str_space = 0;

    int done = 0;

    unsigned long space_needed = 0;

    unsigned long string_offset = 0;

    Dwarf_Small *return_data = 0;

    Dwarf_Small *pdata = 0;

    unsigned long final_count = 0;

    Dwarf_Signed fileindex = -1;

    Dwarf_Small *latest_str_loc = 0;

    struct macro_stack_s msdata;

    unsigned long count = 0;

    unsigned long max_count = (unsigned long) maximum_count;

    _dwarf_reset_index_macro_stack(&msdata);

    if (dbg == NULL) {

	_dwarf_error(NULL, error, DW_DLE_DBG_NULL);

	free_macro_stack(dbg,&msdata);

	return (DW_DLV_ERROR);

    }

    res =

	_dwarf_load_section(dbg,

			    dbg->de_debug_macinfo_index,

			    &dbg->de_debug_macinfo, error);

    if (res != DW_DLV_OK) {

	free_macro_stack(dbg,&msdata);

	return res;

    }

    macro_base = dbg->de_debug_macinfo;

    if (macro_base == NULL) {

	free_macro_stack(dbg,&msdata);

	return (DW_DLV_NO_ENTRY);

    }

    if (macro_offset >= dbg->de_debug_macinfo_size) {

	free_macro_stack(dbg,&msdata);

	return (DW_DLV_NO_ENTRY);

    }

    pnext = macro_base + macro_offset;

    if (maximum_count == 0) {

	max_count = ULONG_MAX;

    }

    /* how many entries and how much space will they take? */

    endloc = (pnext - macro_base);

    if (endloc >= dbg->de_debug_macinfo_size) {

	if (endloc == dbg->de_debug_macinfo_size) {

	    /* normal: found last entry */

	    free_macro_stack(dbg,&msdata);

	    return DW_DLV_NO_ENTRY;

	}

	_dwarf_error(dbg, error, DW_DLE_DEBUG_MACRO_LENGTH_BAD);

	free_macro_stack(dbg,&msdata);

	return (DW_DLV_ERROR);

    }

    for (count = 0; !done && count < max_count; ++count) {

	unsigned long slen;

	Dwarf_Word len;

	uc = *pnext;

	++pnext;		/* get past the type code */

	switch (uc) {

	case DW_MACINFO_define:

	case DW_MACINFO_undef:

	    /* line, string */

	case DW_MACINFO_vendor_ext:

	    /* number, string */

	    (void) _dwarf_decode_u_leb128(pnext, &len);

	    pnext += len;

	    if (((pnext - macro_base)) >= dbg->de_debug_macinfo_size) {

		free_macro_stack(dbg,&msdata);

		_dwarf_error(dbg, error,

			     DW_DLE_DEBUG_MACRO_INCONSISTENT);

		return (DW_DLV_ERROR);

	    }

	    slen = strlen((char *) pnext) + 1;

	    pnext += slen;

	    if (((pnext - macro_base)) >= dbg->de_debug_macinfo_size) {

		free_macro_stack(dbg,&msdata);

		_dwarf_error(dbg, error,

			     DW_DLE_DEBUG_MACRO_INCONSISTENT);

		return (DW_DLV_ERROR);

	    }

	    str_space += slen;

	    break;

	case DW_MACINFO_start_file:

	    /* line, file index */

	    (void) _dwarf_decode_u_leb128(pnext, &len);

	    pnext += len;

	    if (((pnext - macro_base)) >= dbg->de_debug_macinfo_size) {

		free_macro_stack(dbg,&msdata);

		_dwarf_error(dbg, error,

			     DW_DLE_DEBUG_MACRO_INCONSISTENT);

		return (DW_DLV_ERROR);

	    }

	    (void) _dwarf_decode_u_leb128(pnext, &len);

	    pnext += len;

	    if (((pnext - macro_base)) >= dbg->de_debug_macinfo_size) {

		free_macro_stack(dbg,&msdata);

		_dwarf_error(dbg, error,

			     DW_DLE_DEBUG_MACRO_INCONSISTENT);

		return (DW_DLV_ERROR);

	    }

	    ++depth;

	    break;

	case DW_MACINFO_end_file:

	    if (--depth == 0) {

		/* done = 1; no, do not stop here, at least one gcc had 

		   the wrong depth settings in the gcc 3.4 timeframe. */

	    }

	    break;		/* no string or number here */

	case 0:

	    /* end of cu's entries */

	    done = 1;

	    break;

	default:

	    free_macro_stack(dbg,&msdata);

	    _dwarf_error(dbg, error, DW_DLE_DEBUG_MACRO_INCONSISTENT);

	    return (DW_DLV_ERROR);

	    /* bogus macinfo! */

	}

	endloc = (pnext - macro_base);

	if (endloc == dbg->de_debug_macinfo_size) {

	    done = 1;

	} else if (endloc > dbg->de_debug_macinfo_size) {

	    _dwarf_error(dbg, error, DW_DLE_DEBUG_MACRO_LENGTH_BAD);

	    free_macro_stack(dbg,&msdata);

	    return (DW_DLV_ERROR);

	}

    }

    if (count == 0) {

	free_macro_stack(dbg,&msdata);

	_dwarf_error(dbg, error, DW_DLE_DEBUG_MACRO_INTERNAL_ERR);

	return (DW_DLV_ERROR);

    }

    /* we have 'count' array entries to allocate and str_space bytes of 

       string space to provide for. */

    string_offset = count * sizeof(Dwarf_Macro_Details);

    /* extra 2 not really needed */

    space_needed = string_offset + str_space + 2;

    return_data = pdata =

	_dwarf_get_alloc(dbg, DW_DLA_STRING, space_needed);

    latest_str_loc = pdata + string_offset;

    if (pdata == 0) {

	free_macro_stack(dbg,&msdata);

	_dwarf_error(dbg, error, DW_DLE_DEBUG_MACRO_MALLOC_SPACE);

	return (DW_DLV_ERROR);

    }

    pnext = macro_base + macro_offset;

    done = 0;

    /* A series ends with a type code of 0. */

    for (final_count = 0; !done && final_count < count; ++final_count) {

	unsigned long slen;

	Dwarf_Word len;

	Dwarf_Unsigned v1;

	Dwarf_Macro_Details *pdmd = (Dwarf_Macro_Details *) (pdata +

		(final_count * sizeof (Dwarf_Macro_Details)));

	endloc = (pnext - macro_base);

	if (endloc > dbg->de_debug_macinfo_size) {

	    free_macro_stack(dbg,&msdata);

	    _dwarf_error(dbg, error, DW_DLE_DEBUG_MACRO_LENGTH_BAD);

	    return (DW_DLV_ERROR);

	}

	uc = *pnext;

	pdmd->dmd_offset = (pnext - macro_base);

	pdmd->dmd_type = uc;

	pdmd->dmd_fileindex = fileindex;

	pdmd->dmd_lineno = 0;

	pdmd->dmd_macro = 0;

	++pnext;		/* get past the type code */

	switch (uc) {

	case DW_MACINFO_define:

	case DW_MACINFO_undef:

	    /* line, string */

	case DW_MACINFO_vendor_ext:

	    /* number, string */

	    v1 = _dwarf_decode_u_leb128(pnext, &len);

	    pdmd->dmd_lineno = v1;

	    pnext += len;

	    if (((pnext - macro_base)) >= dbg->de_debug_macinfo_size) {

		free_macro_stack(dbg,&msdata);

                dwarf_dealloc(dbg, return_data, DW_DLA_STRING);

		_dwarf_error(dbg, error,

			     DW_DLE_DEBUG_MACRO_INCONSISTENT);

		return (DW_DLV_ERROR);

	    }

	    slen = strlen((char *) pnext) + 1;

	    strcpy((char *) latest_str_loc, (char *) pnext);

	    pdmd->dmd_macro = (char *) latest_str_loc;

	    latest_str_loc += slen;

	    pnext += slen;

	    if (((pnext - macro_base)) >= dbg->de_debug_macinfo_size) {

		free_macro_stack(dbg,&msdata);

                dwarf_dealloc(dbg, return_data, DW_DLA_STRING);

		_dwarf_error(dbg, error,

			     DW_DLE_DEBUG_MACRO_INCONSISTENT);

		return (DW_DLV_ERROR);

	    }

	    break;

	case DW_MACINFO_start_file:

	    /* Line, file index */

	    v1 = _dwarf_decode_u_leb128(pnext, &len);

	    pdmd->dmd_lineno = v1;

	    pnext += len;

	    if (((pnext - macro_base)) >= dbg->de_debug_macinfo_size) {

		free_macro_stack(dbg,&msdata);

                dwarf_dealloc(dbg, return_data, DW_DLA_STRING);

		_dwarf_error(dbg, error,

			     DW_DLE_DEBUG_MACRO_INCONSISTENT);

		return (DW_DLV_ERROR);

	    }

	    v1 = _dwarf_decode_u_leb128(pnext, &len);

	    pdmd->dmd_fileindex = v1;

	    (void) _dwarf_macro_stack_push_index(dbg, fileindex,

						 &msdata);

	    /* We ignore the error, we just let fileindex ** be -1 when 

	       we pop this one. */

	    fileindex = v1;

	    pnext += len;

	    if (((pnext - macro_base)) >= dbg->de_debug_macinfo_size) {

		free_macro_stack(dbg,&msdata);

                dwarf_dealloc(dbg, return_data, DW_DLA_STRING);

		_dwarf_error(dbg, error,

			     DW_DLE_DEBUG_MACRO_INCONSISTENT);

		return (DW_DLV_ERROR);

	    }

	    break;

	case DW_MACINFO_end_file:

	    fileindex = _dwarf_macro_stack_pop_index(&msdata);

	    break;		/* no string or number here */

	case 0:

	    /* Type code of 0 means the end of cu's entries. */

	    done = 1;

	    break;

	default:

	    /* Bogus macinfo! */

            dwarf_dealloc(dbg, return_data, DW_DLA_STRING);

	    free_macro_stack(dbg,&msdata);

	    _dwarf_error(dbg, error, DW_DLE_DEBUG_MACRO_INCONSISTENT);

	    return (DW_DLV_ERROR);

	}

    }

    *entry_count = count;

    *details = (Dwarf_Macro_Details *) return_data;

    free_macro_stack(dbg,&msdata);

    return DW_DLV_OK;

}