Skip to content

Commit

Permalink
Improvements(?) to DWARF handling
Browse files Browse the repository at this point in the history
  • Loading branch information
@mubes
mubes committed Jul 28, 2023
1 parent f63b743 commit 8b3c198
Show file tree
Hide file tree
Showing 4 changed files with 135 additions and 55 deletions.
2 changes: 1 addition & 1 deletion .github/workflows/build-linux.yml
View file
Original file line number Diff line number Diff line change
Expand Up @@ -8,7 +8,7 @@ jobs:
linux:
runs-on: ubuntu-latest
steps:
- run: sudo apt-get install -y libusb-1.0-0-dev libzmq3-dev meson libsdl2-dev libdw-dev libelf-dev libcapstone-dev
- run: sudo apt-get install -y libusb-1.0-0-dev libzmq3-dev meson libsdl2-dev libdwarf-dev libdw-dev libelf-dev libcapstone-dev

- uses: actions/checkout@v3
- run: meson setup ./build
Expand Down
2 changes: 2 additions & 0 deletions Inc/loadelf.h
View file
Original file line number Diff line number Diff line change
@@ -1,3 +1,4 @@

#ifndef _LOADELF_H_

#include <stdbool.h>
Expand Down Expand Up @@ -44,6 +45,7 @@ struct symbolFunctionStore
unsigned int endline; /* End line in source file of function */
symbolMemaddr lowaddr; /* Lowest address of function */
symbolMemaddr highaddr; /* Highest address of function */
bool isinline; /* Is this an abstract template for a function? */
struct symbolLineStore **line; /* Lines comprising this function */
unsigned int nlines; /* Number of lines in line number storage */
};
Expand Down
177 changes: 127 additions & 50 deletions Src/loadelf.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -218,6 +218,44 @@ int _findOrAddString( const char *stringToFindorAdd, char ***table, unsigned int

// ====================================================================================================

#ifdef TESTING_LOADELF
static void _dump_die_attribs( Dwarf_Debug dbg, Dwarf_Die die )

{
Dwarf_Attribute *attrs;
Dwarf_Signed attr_count;
const char *name;

if ( DW_DLV_OK != dwarf_attrlist( die, &attrs, &attr_count, 0 ) )
{
fprintf( stderr, "Requesting attributes failed\n" );
return;
}

// Iterate through attributes
for ( int i = 0; i < attr_count; ++i )
{
Dwarf_Half attr;
Dwarf_Attribute attr_ptr = attrs[i];

if ( DW_DLV_OK != dwarf_whatattr( attr_ptr, &attr, 0 ) )
{
fprintf( stderr, "Failed to itentify attribute\n" );
goto terminate;
}

dwarf_get_AT_name( attr, &name );
printf( "Attribute Name: %s\n", name );
}

// Free attribute list
terminate:
dwarf_dealloc( dbg, attrs, DW_DLA_LIST );
}
#endif

// ====================================================================================================

static void _getSourceLines( struct symbol *p, Dwarf_Debug dbg, Dwarf_Die die )


Expand All @@ -228,29 +266,49 @@ static void _getSourceLines( struct symbol *p, Dwarf_Debug dbg, Dwarf_Die die )
Dwarf_Signed linecount;
Dwarf_Small tc;
Dwarf_Addr line_addr;
Dwarf_Addr tracked_addr;
bool zero_start_dont_store;
char *file_name;
Dwarf_Unsigned line_num;
Dwarf_Bool begin;


/* Now, for each source line, pull it into the line storage */
if ( DW_DLV_OK == dwarf_srclines_b( die, &version, &tc, &linecontext, 0 ) )
{
dwarf_srclines_from_linecontext( linecontext, &linebuf, &linecount, 0 );
tracked_addr = 0;
zero_start_dont_store = true;

/* If a context starts at zero, or is a direct continuation of a context that started at zero, then we dispose of it */
/* We consider any line that is within 16 bytes of the previous one to be a continuation, to allow for padding. */
for ( int i = 0; i < linecount; ++i )
{
// Get the line number and the corresponding address
dwarf_lineno( linebuf[i], &line_num, 0 );
dwarf_lineaddr( linebuf[i], &line_addr, 0 );
dwarf_linesrc( linebuf[i], &file_name, 0 );

p->line = ( struct symbolLineStore ** )realloc( p->line, sizeof( struct symbolLineStore * ) * ( p->nlines + 1 ) );
struct symbolLineStore *newLine = p->line[p->nlines] = ( struct symbolLineStore * )calloc( 1, sizeof( struct symbolLineStore ) );
p->nlines++;
newLine->startline = line_num;
newLine->lowaddr = line_addr;
newLine->isinline = true;
newLine->filename = _findOrAddString( file_name, &p->stringTable[PT_FILENAME], &p->tableLen[PT_FILENAME] );
dwarf_linebeginstatement( linebuf[i], &begin, 0 );

if ( ( zero_start_dont_store && ( ( !begin ) || ( !line_addr ) || ( ( line_addr - tracked_addr ) < 16 ) ) ) ||
( begin && ( line_addr == 0 ) ) )
{
zero_start_dont_store = true;
}
else
{
/* We are going to store this one */
zero_start_dont_store = false;
dwarf_lineno( linebuf[i], &line_num, 0 );
dwarf_linesrc( linebuf[i], &file_name, 0 );

p->line = ( struct symbolLineStore ** )realloc( p->line, sizeof( struct symbolLineStore * ) * ( p->nlines + 1 ) );
struct symbolLineStore *newLine = p->line[p->nlines] = ( struct symbolLineStore * )calloc( 1, sizeof( struct symbolLineStore ) );
p->nlines++;
newLine->startline = line_num;
newLine->lowaddr = line_addr;
newLine->isinline = true;
newLine->filename = _findOrAddString( file_name, &p->stringTable[PT_FILENAME], &p->tableLen[PT_FILENAME] );
}

tracked_addr = line_addr;
}

dwarf_srclines_dealloc_b( linecontext );
Expand All @@ -259,39 +317,60 @@ static void _getSourceLines( struct symbol *p, Dwarf_Debug dbg, Dwarf_Die die )

// ====================================================================================================

static void _processFunctionDie( struct symbol *p, Dwarf_Debug dbg, Dwarf_Die die, int filenameN, int producerN )
void _dwarf_error( Dwarf_Error e, void *ptr )
{
printf( "Reached error:%s\n", dwarf_errmsg( e ) );
exit( -1 );
}

// ====================================================================================================

static void _processFunctionDie( struct symbol *p, Dwarf_Debug dbg, Dwarf_Die die, int filenameN, int producerN, Dwarf_Addr cu_base_addr )

{
char *name = NULL;
Dwarf_Addr h = 0;
Dwarf_Addr l = 0;
char *name;
Dwarf_Addr h;
Dwarf_Addr l;
Dwarf_Attribute attr_data;
Dwarf_Half attr_tag;
bool isinline = false;
struct symbolFunctionStore *newFunc;


dwarf_highpc ( die, &h, 0 );
dwarf_lowpc ( die, &l, 0 );
attr_tag = DW_AT_inline;

if ( l && ( l != h ) )
if ( dwarf_attr( die, attr_tag, &attr_data, 0 ) == DW_DLV_OK )
{
/* This has length, so it's valid ... create a new function entry */
if ( DW_DLV_OK != dwarf_diename( die, &name, 0 ) )
{
attr_tag = DW_AT_abstract_origin;
return;
}

if ( dwarf_attr( die, attr_tag, &attr_data, 0 ) == DW_DLV_OK )
{
Dwarf_Off abstract_origin_offset;
Dwarf_Die abstract_origin_die;
dwarf_global_formref( attr_data, &abstract_origin_offset, 0 );
dwarf_offdie( dbg, abstract_origin_offset, &abstract_origin_die, 0 );
dwarf_diename( abstract_origin_die, &name, 0 );
}
}
/* See if this is an inline die usage */
attr_tag = DW_AT_abstract_origin;

if ( dwarf_attr( die, attr_tag, &attr_data, 0 ) == DW_DLV_OK )
{
/* It is, so track back to the real one */
Dwarf_Off abstract_origin_offset;
attr_tag = DW_AT_abstract_origin;
dwarf_attr( die, attr_tag, &attr_data, 0 );
dwarf_global_formref( attr_data, &abstract_origin_offset, 0 );
dwarf_offdie( dbg, abstract_origin_offset, &die, 0 );
//printf("Instance at %08x...%08x\n\n\n",(uint32_t)l,(uint32_t)h);
isinline = true;
}
else
{
dwarf_highpc ( die, &h, 0 );
dwarf_lowpc ( die, &l, 0 );
}

if ( l && ( l != h ) )
{
dwarf_diename( die, &name, 0 );

p->func = ( struct symbolFunctionStore ** )realloc( p->func, sizeof( struct symbolFunctionStore * ) * ( p->nfunc + 1 ) );
newFunc = p->func[p->nfunc] = ( struct symbolFunctionStore * )calloc( 1, sizeof( struct symbolFunctionStore ) );
newFunc->isinline = isinline;
p->nfunc++;

newFunc->funcname = strdup( name );
Expand Down Expand Up @@ -323,43 +402,42 @@ static void _processFunctionDie( struct symbol *p, Dwarf_Debug dbg, Dwarf_Die di

// ====================================================================================================

static void _processDie( struct symbol *p, Dwarf_Debug dbg, Dwarf_Die die, int level, int filenameN, int producerN )
static void _processDie( struct symbol *p, Dwarf_Debug dbg, Dwarf_Die die, int level, int filenameN, int producerN, Dwarf_Addr cu_base_addr )

{
Dwarf_Error err;
Dwarf_Half tag;

dwarf_tag( die, &tag, &err );
dwarf_tag( die, &tag, 0 );

if ( tag == DW_TAG_subprogram )
if ( ( tag == DW_TAG_subprogram ) || ( tag == DW_TAG_inlined_subroutine ) )
{
_processFunctionDie( p, dbg, die, filenameN, producerN );
_processFunctionDie( p, dbg, die, filenameN, producerN, cu_base_addr );
}

// Recursively process children DIEs
Dwarf_Die child;

int res = dwarf_child( die, &child, &err );
int res = dwarf_child( die, &child, 0 );

if ( res == DW_DLV_OK )
{
do
{
_processDie( p, dbg, child, level + 1, filenameN, producerN );
_processDie( p, dbg, child, level + 1, filenameN, producerN, cu_base_addr );

}
while ( dwarf_siblingof( dbg, child, &child, &err ) == DW_DLV_OK );
while ( dwarf_siblingof( dbg, child, &child, 0 ) == DW_DLV_OK );
}
}
// ====================================================================================================

static bool _readLines( int fd, struct symbol *p )
{
Dwarf_Debug dbg;
Dwarf_Error err;
Dwarf_Unsigned cu_header_length;
Dwarf_Half version_stamp;
Dwarf_Off abbrev_offset;
Dwarf_Addr cu_low_addr;
Dwarf_Half address_size;
Dwarf_Unsigned next_cu_header = 0;
Dwarf_Die cu_die;
Expand All @@ -371,7 +449,7 @@ static bool _readLines( int fd, struct symbol *p )
unsigned int filenameN;
unsigned int producerN;

if ( 0 != dwarf_init( fd, DW_DLC_READ, NULL, NULL, &dbg, &err ) )
if ( 0 != dwarf_init( fd, DW_DLC_READ, &_dwarf_error, NULL, &dbg, 0 ) )
{
return false;
}
Expand All @@ -384,13 +462,12 @@ static bool _readLines( int fd, struct symbol *p )

/* 1: Collect the functions and lines */
/* ---------------------------------- */
while ( ( 0 == dwarf_next_cu_header( dbg, &cu_header_length, &version_stamp, &abbrev_offset, &address_size, &next_cu_header, &err ) ) )
while ( ( 0 == dwarf_next_cu_header( dbg, &cu_header_length, &version_stamp, &abbrev_offset, &address_size, &next_cu_header, 0 ) ) )
{
dwarf_siblingof( dbg, NULL, &cu_die, &err );
dwarf_diename( cu_die, &name, &err );
dwarf_die_text( cu_die, DW_AT_producer, &producer, &err );
dwarf_die_text( cu_die, DW_AT_comp_dir, &compdir, &err );

dwarf_siblingof( dbg, NULL, &cu_die, 0 );
dwarf_diename( cu_die, &name, 0 );
dwarf_die_text( cu_die, DW_AT_producer, &producer, 0 );
dwarf_die_text( cu_die, DW_AT_comp_dir, &compdir, 0 );

/* Need to construct the fully qualified filename from the directory + filename */
char *s = ( char * )malloc( strlen( name ) + strlen( compdir ) + 2 );
Expand All @@ -402,7 +479,9 @@ static bool _readLines( int fd, struct symbol *p )
producerN = _findOrAddString( producer, &p->stringTable[PT_PRODUCER], &p->tableLen[PT_PRODUCER] );

/* Kickoff the process for the DIE and its children to get the functions in this cu */
_processDie( p, dbg, cu_die, 0, filenameN, producerN );

dwarf_lowpc( cu_die, &cu_low_addr, 0 );
_processDie( p, dbg, cu_die, 0, filenameN, producerN, cu_low_addr );

/* ...and the source lines */
_getSourceLines( p, dbg, cu_die );
Expand Down Expand Up @@ -1045,8 +1124,6 @@ void main( int argc, char *argv[] )
exit( -1 );
}

// _listFunctions(p,false);
// exit(-1);
struct symbolLineStore *s;

for ( int i = 0; i < p->nlines; i++ )
Expand Down
9 changes: 5 additions & 4 deletions Src/sio.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -43,7 +43,7 @@ enum CP
CP_FG_BRIGHT_WHITE,

/* Remaining pairs */
CP_EVENT, CP_NORMAL, CP_FILEFUNCTION, CP_LINENO, CP_EXECASSY, CP_NEXECASSY, CP_BASELINE, CP_BASELINETEXT, CP_SEARCH, CP_DEBUG
CP_EVENT, CP_NORMAL, CP_FILEFUNCTION, CP_LINENO, CP_EXECASSY, CP_NEXECASSY, CP_BASELINE, CP_BASELINETEXT, CP_SEARCH, CP_DEBUG, CP_SOURCEHL
};

/* Search types */
Expand Down Expand Up @@ -620,20 +620,20 @@ static bool _displayLine( struct SIOInstance *sio, int32_t lineNum, int32_t scre
if ( !strncmp( u, "[m", 2 ) )
{
u += 2;
wattrset( sio->outputWindow, ( highlight ? A_STANDOUT : 0 ) | COLOR_PAIR( 15 ) );
wattrset( sio->outputWindow, ( highlight ? A_BOLD | A_STANDOUT | COLOR_PAIR( CP_SOURCEHL ) : COLOR_PAIR( 15 ) ) );
continue;
}

if ( !strncmp( u, "[3", 2 ) )
{
wattrset( sio->outputWindow, ( highlight ? A_STANDOUT : 0 ) | COLOR_PAIR( ( *( u + 2 ) ) - '0' ) );
wattrset( sio->outputWindow, ( highlight ? A_BOLD | A_STANDOUT | COLOR_PAIR( CP_SOURCEHL ) : COLOR_PAIR( ( *( u + 2 ) ) - '0' ) ) );
u += 4;
continue;
}

if ( !strncmp( u, "[01;3", 5 ) )
{
wattrset( sio->outputWindow, ( highlight ? A_STANDOUT : 0 ) | COLOR_PAIR( ( *( u + 5 ) ) - '0' ) );
wattrset( sio->outputWindow, ( highlight ? A_BOLD | A_STANDOUT | COLOR_PAIR( CP_SOURCEHL ) : COLOR_PAIR( ( *( u + 5 ) ) - '0' ) ) );
u += 7;
continue;
}
Expand Down Expand Up @@ -934,6 +934,7 @@ struct SIOInstance *SIOsetup( const char *progname, const char *elffile, bool is
init_pair( CP_BASELINETEXT, COLOR_YELLOW, COLOR_BLACK );
init_pair( CP_SEARCH, COLOR_GREEN, COLOR_BLACK );
init_pair( CP_DEBUG, COLOR_MAGENTA, COLOR_BLACK );
init_pair( CP_SOURCEHL, COLOR_WHITE, COLOR_BLACK );
}

sio->outputWindow = newwin( OUTPUT_WINDOW_L, OUTPUT_WINDOW_W, 0, 0 );
Expand Down

0 comments on commit 8b3c198

Please sign in to comment.