diff options
Diffstat (limited to 'libdw/dwarf_getsrclines.c')
| -rw-r--r-- | libdw/dwarf_getsrclines.c | 753 |
1 files changed, 753 insertions, 0 deletions
diff --git a/libdw/dwarf_getsrclines.c b/libdw/dwarf_getsrclines.c new file mode 100644 index 0000000..6840b2b --- /dev/null +++ b/libdw/dwarf_getsrclines.c @@ -0,0 +1,753 @@ +/* Return line number information of CU. + Copyright (C) 2004-2010 Red Hat, Inc. + This file is part of Red Hat elfutils. + Written by Ulrich Drepper <drepper@redhat.com>, 2004. + + Red Hat elfutils is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by the + Free Software Foundation; version 2 of the License. + + Red Hat elfutils 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 + General Public License for more details. + + You should have received a copy of the GNU General Public License along + with Red Hat elfutils; if not, write to the Free Software Foundation, + Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA. + + In addition, as a special exception, Red Hat, Inc. gives You the + additional right to link the code of Red Hat elfutils with code licensed + under any Open Source Initiative certified open source license + (http://www.opensource.org/licenses/index.php) which requires the + distribution of source code with any binary distribution and to + distribute linked combinations of the two. Non-GPL Code permitted under + this exception must only link to the code of Red Hat elfutils through + those well defined interfaces identified in the file named EXCEPTION + found in the source code files (the "Approved Interfaces"). The files + of Non-GPL Code may instantiate templates or use macros or inline + functions from the Approved Interfaces without causing the resulting + work to be covered by the GNU General Public License. Only Red Hat, + Inc. may make changes or additions to the list of Approved Interfaces. + Red Hat's grant of this exception is conditioned upon your not adding + any new exceptions. If you wish to add a new Approved Interface or + exception, please contact Red Hat. You must obey the GNU General Public + License in all respects for all of the Red Hat elfutils code and other + code used in conjunction with Red Hat elfutils except the Non-GPL Code + covered by this exception. If you modify this file, you may extend this + exception to your version of the file, but you are not obligated to do + so. If you do not wish to provide this exception without modification, + you must delete this exception statement from your version and license + this file solely under the GPL without exception. + + Red Hat elfutils is an included package of the Open Invention Network. + An included package of the Open Invention Network is a package for which + Open Invention Network licensees cross-license their patents. No patent + license is granted, either expressly or impliedly, by designation as an + included package. Should you wish to participate in the Open Invention + Network licensing program, please visit www.openinventionnetwork.com + <http://www.openinventionnetwork.com>. */ + +#ifdef HAVE_CONFIG_H +# include <config.h> +#endif + +#include <assert.h> +#include <stdlib.h> +#include <string.h> +#include "dwarf.h" +#include "libdwP.h" + + +struct filelist +{ + Dwarf_Fileinfo info; + struct filelist *next; +}; + +struct linelist +{ + Dwarf_Line line; + struct linelist *next; +}; + + +/* Compare by Dwarf_Line.addr, given pointers into an array of pointers. */ +static int +compare_lines (const void *a, const void *b) +{ + Dwarf_Line *const *p1 = a; + Dwarf_Line *const *p2 = b; + + if ((*p1)->addr == (*p2)->addr) + /* An end_sequence marker precedes a normal record at the same address. */ + return (*p2)->end_sequence - (*p1)->end_sequence; + + return (*p1)->addr - (*p2)->addr; +} + +int +dwarf_getsrclines (Dwarf_Die *cudie, Dwarf_Lines **lines, size_t *nlines) +{ + if (unlikely (cudie == NULL + || INTUSE(dwarf_tag) (cudie) != DW_TAG_compile_unit)) + return -1; + + int res = -1; + + /* Get the information if it is not already known. */ + struct Dwarf_CU *const cu = cudie->cu; + if (cu->lines == NULL) + { + /* Failsafe mode: no data found. */ + cu->lines = (void *) -1l; + cu->files = (void *) -1l; + + /* The die must have a statement list associated. */ + Dwarf_Attribute stmt_list_mem; + Dwarf_Attribute *stmt_list = INTUSE(dwarf_attr) (cudie, DW_AT_stmt_list, + &stmt_list_mem); + + /* Get the offset into the .debug_line section. NB: this call + also checks whether the previous dwarf_attr call failed. */ + const unsigned char *lineendp; + const unsigned char *linep + = __libdw_formptr (stmt_list, IDX_debug_line, DWARF_E_NO_DEBUG_LINE, + (unsigned char **) &lineendp, NULL); + if (linep == NULL) + goto out; + + /* Get the compilation directory. */ + Dwarf_Attribute compdir_attr_mem; + Dwarf_Attribute *compdir_attr = INTUSE(dwarf_attr) (cudie, + DW_AT_comp_dir, + &compdir_attr_mem); + const char *comp_dir = INTUSE(dwarf_formstring) (compdir_attr); + + if (unlikely (linep + 4 > lineendp)) + { + invalid_data: + __libdw_seterrno (DWARF_E_INVALID_DEBUG_LINE); + goto out; + } + + Dwarf *dbg = cu->dbg; + Dwarf_Word unit_length = read_4ubyte_unaligned_inc (dbg, linep); + unsigned int length = 4; + if (unlikely (unit_length == DWARF3_LENGTH_64_BIT)) + { + if (unlikely (linep + 8 > lineendp)) + goto invalid_data; + unit_length = read_8ubyte_unaligned_inc (dbg, linep); + length = 8; + } + + /* Check whether we have enough room in the section. */ + if (unit_length < 2 + length + 5 * 1 + || unlikely (linep + unit_length > lineendp)) + goto invalid_data; + lineendp = linep + unit_length; + + /* The next element of the header is the version identifier. */ + uint_fast16_t version = read_2ubyte_unaligned_inc (dbg, linep); + if (unlikely (version < 2) || unlikely (version > 4)) + { + __libdw_seterrno (DWARF_E_VERSION); + goto out; + } + + /* Next comes the header length. */ + Dwarf_Word header_length; + if (length == 4) + header_length = read_4ubyte_unaligned_inc (dbg, linep); + else + header_length = read_8ubyte_unaligned_inc (dbg, linep); + const unsigned char *header_start = linep; + + /* Next the minimum instruction length. */ + uint_fast8_t minimum_instr_len = *linep++; + + /* Next the maximum operations per instruction, in version 4 format. */ + uint_fast8_t max_ops_per_instr = 1; + if (version >= 4) + { + if (unlikely (lineendp - linep < 5)) + goto invalid_data; + max_ops_per_instr = *linep++; + if (unlikely (max_ops_per_instr == 0)) + goto invalid_data; + } + + /* Then the flag determining the default value of the is_stmt + register. */ + uint_fast8_t default_is_stmt = *linep++; + + /* Now the line base. */ + int_fast8_t line_base = (int8_t) *linep++; + + /* And the line range. */ + uint_fast8_t line_range = *linep++; + + /* The opcode base. */ + uint_fast8_t opcode_base = *linep++; + + /* Remember array with the standard opcode length (-1 to account for + the opcode with value zero not being mentioned). */ + const uint8_t *standard_opcode_lengths = linep - 1; + if (unlikely (lineendp - linep < opcode_base - 1)) + goto invalid_data; + linep += opcode_base - 1; + + /* First comes the list of directories. Add the compilation + directory first since the index zero is used for it. */ + struct dirlist + { + const char *dir; + size_t len; + struct dirlist *next; + } comp_dir_elem = + { + .dir = comp_dir, + .len = comp_dir ? strlen (comp_dir) : 0, + .next = NULL + }; + struct dirlist *dirlist = &comp_dir_elem; + unsigned int ndirlist = 1; + + // XXX Directly construct array to conserve memory? + while (*linep != 0) + { + struct dirlist *new_dir = + (struct dirlist *) alloca (sizeof (*new_dir)); + + new_dir->dir = (char *) linep; + uint8_t *endp = memchr (linep, '\0', lineendp - linep); + if (endp == NULL) + goto invalid_data; + new_dir->len = endp - linep; + new_dir->next = dirlist; + dirlist = new_dir; + ++ndirlist; + linep = endp + 1; + } + /* Skip the final NUL byte. */ + ++linep; + + /* Rearrange the list in array form. */ + struct dirlist **dirarray + = (struct dirlist **) alloca (ndirlist * sizeof (*dirarray)); + for (unsigned int n = ndirlist; n-- > 0; dirlist = dirlist->next) + dirarray[n] = dirlist; + + /* Now read the files. */ + struct filelist null_file = + { + .info = + { + .name = "???", + .mtime = 0, + .length = 0 + }, + .next = NULL + }; + struct filelist *filelist = &null_file; + unsigned int nfilelist = 1; + + if (unlikely (linep >= lineendp)) + goto invalid_data; + while (*linep != 0) + { + struct filelist *new_file = + (struct filelist *) alloca (sizeof (*new_file)); + + /* First comes the file name. */ + char *fname = (char *) linep; + uint8_t *endp = memchr (fname, '\0', lineendp - linep); + if (endp == NULL) + goto invalid_data; + size_t fnamelen = endp - (uint8_t *) fname; + linep = endp + 1; + + /* Then the index. */ + Dwarf_Word diridx; + get_uleb128 (diridx, linep); + if (unlikely (diridx >= ndirlist)) + { + __libdw_seterrno (DWARF_E_INVALID_DIR_IDX); + goto out; + } + + if (*fname == '/') + /* It's an absolute path. */ + new_file->info.name = fname; + else + { + new_file->info.name = libdw_alloc (dbg, char, 1, + dirarray[diridx]->len + 1 + + fnamelen + 1); + char *cp = new_file->info.name; + + if (dirarray[diridx]->dir != NULL) + { + /* This value could be NULL in case the DW_AT_comp_dir + was not present. We cannot do much in this case. + The easiest thing is to convert the path in an + absolute path. */ + cp = stpcpy (cp, dirarray[diridx]->dir); + } + *cp++ = '/'; + strcpy (cp, fname); + assert (strlen (new_file->info.name) + < dirarray[diridx]->len + 1 + fnamelen + 1); + } + + /* Next comes the modification time. */ + get_uleb128 (new_file->info.mtime, linep); + + /* Finally the length of the file. */ + get_uleb128 (new_file->info.length, linep); + + new_file->next = filelist; + filelist = new_file; + ++nfilelist; + } + /* Skip the final NUL byte. */ + ++linep; + + /* Consistency check. */ + if (unlikely (linep != header_start + header_length)) + { + __libdw_seterrno (DWARF_E_INVALID_DWARF); + goto out; + } + + /* We are about to process the statement program. Initialize the + state machine registers (see 6.2.2 in the v2.1 specification). */ + Dwarf_Word addr = 0; + unsigned int op_index = 0; + unsigned int file = 1; + int line = 1; + unsigned int column = 0; + uint_fast8_t is_stmt = default_is_stmt; + bool basic_block = false; + bool prologue_end = false; + bool epilogue_begin = false; + unsigned int isa = 0; + unsigned int discriminator = 0; + + /* Apply the "operation advance" from a special opcode + or DW_LNS_advance_pc (as per DWARF4 6.2.5.1). */ + inline void advance_pc (unsigned int op_advance) + { + addr += minimum_instr_len * ((op_index + op_advance) + / max_ops_per_instr); + op_index = (op_index + op_advance) % max_ops_per_instr; + } + + /* Process the instructions. */ + struct linelist *linelist = NULL; + unsigned int nlinelist = 0; + + /* Adds a new line to the matrix. + We cannot simply define a function because we want to use alloca. */ +#define NEW_LINE(end_seq) \ + do { \ + if (unlikely (add_new_line (alloca (sizeof (struct linelist)), \ + end_seq))) \ + goto invalid_data; \ + } while (0) + + inline bool add_new_line (struct linelist *new_line, bool end_sequence) + { + /* Set the line information. For some fields we use bitfields, + so we would lose information if the encoded values are too large. + Check just for paranoia, and call the data "invalid" if it + violates our assumptions on reasonable limits for the values. */ +#define SET(field) \ + do { \ + new_line->line.field = field; \ + if (unlikely (new_line->line.field != field)) \ + return true; \ + } while (0) + + SET (addr); + SET (op_index); + SET (file); + SET (line); + SET (column); + SET (is_stmt); + SET (basic_block); + SET (end_sequence); + SET (prologue_end); + SET (epilogue_begin); + SET (isa); + SET (discriminator); + +#undef SET + + new_line->next = linelist; + linelist = new_line; + ++nlinelist; + + return false; + } + + while (linep < lineendp) + { + unsigned int opcode; + unsigned int u128; + int s128; + + /* Read the opcode. */ + opcode = *linep++; + + /* Is this a special opcode? */ + if (likely (opcode >= opcode_base)) + { + /* Yes. Handling this is quite easy since the opcode value + is computed with + + opcode = (desired line increment - line_base) + + (line_range * address advance) + opcode_base + */ + int line_increment = (line_base + + (opcode - opcode_base) % line_range); + + /* Perform the increments. */ + line += line_increment; + advance_pc ((opcode - opcode_base) / line_range); + + /* Add a new line with the current state machine values. */ + NEW_LINE (0); + + /* Reset the flags. */ + basic_block = false; + prologue_end = false; + epilogue_begin = false; + discriminator = 0; + } + else if (opcode == 0) + { + /* This an extended opcode. */ + if (unlikely (lineendp - linep < 2)) + goto invalid_data; + + /* The length. */ + uint_fast8_t len = *linep++; + + if (unlikely ((size_t) (lineendp - linep) < len)) + goto invalid_data; + + /* The sub-opcode. */ + opcode = *linep++; + + switch (opcode) + { + case DW_LNE_end_sequence: + /* Add a new line with the current state machine values. + The is the end of the sequence. */ + NEW_LINE (1); + + /* Reset the registers. */ + addr = 0; + op_index = 0; + file = 1; + line = 1; + column = 0; + is_stmt = default_is_stmt; + basic_block = false; + prologue_end = false; + epilogue_begin = false; + isa = 0; + discriminator = 0; + break; + + case DW_LNE_set_address: + /* The value is an address. The size is defined as + apporiate for the target machine. We use the + address size field from the CU header. */ + op_index = 0; + if (unlikely (lineendp - linep < cu->address_size)) + goto invalid_data; + if (__libdw_read_address_inc (dbg, IDX_debug_line, &linep, + cu->address_size, &addr)) + goto out; + break; + + case DW_LNE_define_file: + { + char *fname = (char *) linep; + uint8_t *endp = memchr (linep, '\0', lineendp - linep); + if (endp == NULL) + goto invalid_data; + size_t fnamelen = endp - linep; + linep = endp + 1; + + unsigned int diridx; + get_uleb128 (diridx, linep); + Dwarf_Word mtime; + get_uleb128 (mtime, linep); + Dwarf_Word filelength; + get_uleb128 (filelength, linep); + + struct filelist *new_file = + (struct filelist *) alloca (sizeof (*new_file)); + if (fname[0] == '/') + new_file->info.name = fname; + else + { + new_file->info.name = + libdw_alloc (dbg, char, 1, (dirarray[diridx]->len + 1 + + fnamelen + 1)); + char *cp = new_file->info.name; + + if (dirarray[diridx]->dir != NULL) + /* This value could be NULL in case the + DW_AT_comp_dir was not present. We + cannot do much in this case. The easiest + thing is to convert the path in an + absolute path. */ + cp = stpcpy (cp, dirarray[diridx]->dir); + *cp++ = '/'; + strcpy (cp, fname); + } + + new_file->info.mtime = mtime; + new_file->info.length = filelength; + new_file->next = filelist; + filelist = new_file; + ++nfilelist; + } + break; + + case DW_LNE_set_discriminator: + /* Takes one ULEB128 parameter, the discriminator. */ + if (unlikely (standard_opcode_lengths[opcode] != 1)) + goto invalid_data; + + get_uleb128 (discriminator, linep); + break; + + default: + /* Unknown, ignore it. */ + if (unlikely ((size_t) (lineendp - (linep - 1)) < len)) + goto invalid_data; + linep += len - 1; + break; + } + } + else if (opcode <= DW_LNS_set_isa) + { + /* This is a known standard opcode. */ + switch (opcode) + { + case DW_LNS_copy: + /* Takes no argument. */ + if (unlikely (standard_opcode_lengths[opcode] != 0)) + goto invalid_data; + + /* Add a new line with the current state machine values. */ + NEW_LINE (0); + + /* Reset the flags. */ + basic_block = false; + prologue_end = false; + epilogue_begin = false; + discriminator = 0; + break; + + case DW_LNS_advance_pc: + /* Takes one uleb128 parameter which is added to the + address. */ + if (unlikely (standard_opcode_lengths[opcode] != 1)) + goto invalid_data; + + get_uleb128 (u128, linep); + advance_pc (u128); + break; + + case DW_LNS_advance_line: + /* Takes one sleb128 parameter which is added to the + line. */ + if (unlikely (standard_opcode_lengths[opcode] != 1)) + goto invalid_data; + + get_sleb128 (s128, linep); + line += s128; + break; + + case DW_LNS_set_file: + /* Takes one uleb128 parameter which is stored in file. */ + if (unlikely (standard_opcode_lengths[opcode] != 1)) + goto invalid_data; + + get_uleb128 (u128, linep); + file = u128; + break; + + case DW_LNS_set_column: + /* Takes one uleb128 parameter which is stored in column. */ + if (unlikely (standard_opcode_lengths[opcode] != 1)) + goto invalid_data; + + get_uleb128 (u128, linep); + column = u128; + break; + + case DW_LNS_negate_stmt: + /* Takes no argument. */ + if (unlikely (standard_opcode_lengths[opcode] != 0)) + goto invalid_data; + + is_stmt = 1 - is_stmt; + break; + + case DW_LNS_set_basic_block: + /* Takes no argument. */ + if (unlikely (standard_opcode_lengths[opcode] != 0)) + goto invalid_data; + + basic_block = true; + break; + + case DW_LNS_const_add_pc: + /* Takes no argument. */ + if (unlikely (standard_opcode_lengths[opcode] != 0)) + goto invalid_data; + + advance_pc ((255 - opcode_base) / line_range); + break; + + case DW_LNS_fixed_advance_pc: + /* Takes one 16 bit parameter which is added to the + address. */ + if (unlikely (standard_opcode_lengths[opcode] != 1) + || unlikely (lineendp - linep < 2)) + goto invalid_data; + + addr += read_2ubyte_unaligned_inc (dbg, linep); + op_index = 0; + break; + + case DW_LNS_set_prologue_end: + /* Takes no argument. */ + if (unlikely (standard_opcode_lengths[opcode] != 0)) + goto invalid_data; + + prologue_end = true; + break; + + case DW_LNS_set_epilogue_begin: + /* Takes no argument. */ + if (unlikely (standard_opcode_lengths[opcode] != 0)) + goto invalid_data; + + epilogue_begin = true; + break; + + case DW_LNS_set_isa: + /* Takes one uleb128 parameter which is stored in isa. */ + if (unlikely (standard_opcode_lengths[opcode] != 1)) + goto invalid_data; + + get_uleb128 (isa, linep); + break; + } + } + else + { + /* This is a new opcode the generator but not we know about. + Read the parameters associated with it but then discard + everything. Read all the parameters for this opcode. */ + for (int n = standard_opcode_lengths[opcode]; n > 0; --n) + get_uleb128 (u128, linep); + + /* Next round, ignore this opcode. */ + continue; + } + } + + /* Put all the files in an array. */ + Dwarf_Files *files = libdw_alloc (dbg, Dwarf_Files, + sizeof (Dwarf_Files) + + nfilelist * sizeof (Dwarf_Fileinfo) + + (ndirlist + 1) * sizeof (char *), + 1); + const char **dirs = (void *) &files->info[nfilelist]; + + files->nfiles = nfilelist; + while (nfilelist-- > 0) + { + files->info[nfilelist] = filelist->info; + filelist = filelist->next; + } + assert (filelist == NULL); + + /* Put all the directory strings in an array. */ + files->ndirs = ndirlist; + for (unsigned int i = 0; i < ndirlist; ++i) + dirs[i] = dirarray[i]->dir; + dirs[ndirlist] = NULL; + + /* Remember the referring CU. */ + files->cu = cu; + + /* Make the file data structure available through the CU. */ + cu->files = files; + + void *buf = libdw_alloc (dbg, Dwarf_Lines, (sizeof (Dwarf_Lines) + + (sizeof (Dwarf_Line) + * nlinelist)), 1); + + /* First use the buffer for the pointers, and sort the entries. + We'll write the pointers in the end of the buffer, and then + copy into the buffer from the beginning so the overlap works. */ + assert (sizeof (Dwarf_Line) >= sizeof (Dwarf_Line *)); + Dwarf_Line **sortlines = (buf + sizeof (Dwarf_Lines) + + ((sizeof (Dwarf_Line) + - sizeof (Dwarf_Line *)) * nlinelist)); + + /* The list is in LIFO order and usually they come in clumps with + ascending addresses. So fill from the back to probably start with + runs already in order before we sort. */ + unsigned int i = nlinelist; + while (i-- > 0) + { + sortlines[i] = &linelist->line; + linelist = linelist->next; + } + assert (linelist == NULL); + + /* Sort by ascending address. */ + qsort (sortlines, nlinelist, sizeof sortlines[0], &compare_lines); + + /* Now that they are sorted, put them in the final array. + The buffers overlap, so we've clobbered the early elements + of SORTLINES by the time we're reading the later ones. */ + cu->lines = buf; + cu->lines->nlines = nlinelist; + for (i = 0; i < nlinelist; ++i) + { + cu->lines->info[i] = *sortlines[i]; + cu->lines->info[i].files = files; + } + + /* Success. */ + res = 0; + } + else if (cu->lines != (void *) -1l) + /* We already have the information. */ + res = 0; + + if (likely (res == 0)) + { + *lines = cu->lines; + *nlines = cu->lines->nlines; + } + out: + + // XXX Eventually: unlocking here. + + return res; +} +INTDEF(dwarf_getsrclines) |