diff options
Diffstat (limited to 'libdw/dwarf_getsrclines.c')
| -rw-r--r-- | libdw/dwarf_getsrclines.c | 652 |
1 files changed, 652 insertions, 0 deletions
diff --git a/libdw/dwarf_getsrclines.c b/libdw/dwarf_getsrclines.c new file mode 100644 index 00000000..37e14aee --- /dev/null +++ b/libdw/dwarf_getsrclines.c @@ -0,0 +1,652 @@ +/* Return line number information of CU. + Copyright (C) 2004, 2005 Red Hat, Inc. + Written by Ulrich Drepper <drepper@redhat.com>, 2004. + + This program is Open Source software; you can redistribute it and/or + modify it under the terms of the Open Software License version 1.0 as + published by the Open Source Initiative. + + You should have received a copy of the Open Software License along + with this program; if not, you may obtain a copy of the Open Software + License version 1.0 from http://www.opensource.org/licenses/osl.php or + by writing the Open Source Initiative c/o Lawrence Rosen, Esq., + 3001 King Ranch Road, Ukiah, CA 95482. */ + +#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; + + return (*p1)->addr - (*p2)->addr; +} + + +/* Adds a new line to the matrix. We cannot define a function because + we want to use alloca. */ +#define NEW_LINE(end_seq) \ + do { \ + /* Add the new line. */ \ + new_line = (struct linelist *) alloca (sizeof (struct linelist)); \ + \ + /* Set the line information. */ \ + new_line->line.addr = address; \ + new_line->line.file = file; \ + new_line->line.line = line; \ + new_line->line.column = column; \ + new_line->line.is_stmt = is_stmt; \ + new_line->line.basic_block = basic_block; \ + new_line->line.end_sequence = end_seq; \ + new_line->line.prologue_end = prologue_end; \ + new_line->line.epilogue_begin = epilogue_begin; \ + \ + new_line->next = linelist; \ + linelist = new_line; \ + ++nlinelist; \ + } while (0) + + +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. */ + Dwarf_Word offset; + if (INTUSE(dwarf_formudata) (stmt_list, &offset) != 0) + goto out; + + Dwarf *dbg = cu->dbg; + if (dbg->sectiondata[IDX_debug_line] == NULL) + { + __libdw_seterrno (DWARF_E_NO_DEBUG_LINE); + goto out; + } + const uint8_t *linep = dbg->sectiondata[IDX_debug_line]->d_buf + offset; + const uint8_t *lineendp = (dbg->sectiondata[IDX_debug_line]->d_buf + + dbg->sectiondata[IDX_debug_line]->d_size); + + /* 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_Word unit_length = read_4ubyte_unaligned_inc (dbg, linep); + unsigned int length = 4; + if (unlikely (unit_length == 0xffffffff)) + { + 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 != DWARF_VERSION)) + { + __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++; + + /* 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 = *((int_fast8_t *) linep); + ++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; + linep += opcode_base - 1; + if (unlikely (linep >= lineendp)) + goto invalid_data; + + /* 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)); + while (ndirlist-- > 0) + { + dirarray[ndirlist] = dirlist; + dirlist = dirlist->next; + } + + /* 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 address = 0; + size_t file = 1; + size_t line = 1; + size_t column = 0; + uint_fast8_t is_stmt = default_is_stmt; + int basic_block = 0; + int prologue_end = 0; + int epilogue_begin = 0; + + /* Process the instructions. */ + struct linelist *linelist = NULL; + unsigned int nlinelist = 0; + while (linep < lineendp) + { + struct linelist *new_line; + 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); + unsigned int address_increment = (minimum_instr_len + * ((opcode - opcode_base) + / line_range)); + + /* Perform the increments. */ + line += line_increment; + address += address_increment; + + /* Add a new line with the current state machine values. */ + NEW_LINE (0); + + /* Reset the flags. */ + basic_block = 0; + prologue_end = 0; + epilogue_begin = 0; + } + else if (opcode == 0) + { + /* This an extended opcode. */ + if (unlikely (linep + 2 > lineendp)) + goto invalid_data; + + /* The length. */ + unsigned int len = *linep++; + + if (unlikely (linep + len > lineendp)) + 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. */ + address = 0; + file = 1; + line = 1; + column = 0; + is_stmt = default_is_stmt; + basic_block = 0; + prologue_end = 0; + epilogue_begin = 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. */ + if (cu->address_size == 4) + address = read_4ubyte_unaligned_inc (dbg, linep); + else + address = read_8ubyte_unaligned_inc (dbg, linep); + 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; + + default: + /* Unknown, ignore it. */ + linep += len - 1; + break; + } + } + else if (opcode <= DW_LNS_set_epilog_begin) + { + /* 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 = 0; + /* XXX Whether the following two lines are necessary is + unclear. I guess the current v2.1 specification has + a bug in that it says clearing these two registers is + not necessary. */ + prologue_end = 0; + epilogue_begin = 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); + address += minimum_instr_len * 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 = 1; + break; + + case DW_LNS_const_add_pc: + /* Takes no argument. */ + if (unlikely (standard_opcode_lengths[opcode] != 0)) + goto invalid_data; + + address += (minimum_instr_len + * ((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)) + goto invalid_data; + + address += read_2ubyte_unaligned_inc (dbg, linep); + break; + + case DW_LNS_set_prologue_end: + /* Takes no argument. */ + if (unlikely (standard_opcode_lengths[opcode] != 0)) + goto invalid_data; + + prologue_end = 1; + break; + + case DW_LNS_set_epilog_begin: + /* Takes no argument. */ + if (unlikely (standard_opcode_lengths[opcode] != 0)) + goto invalid_data; + + epilogue_begin = 1; + 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), + 1); + files->nfiles = nfilelist; + while (nfilelist-- > 0) + { + files->info[nfilelist] = filelist->info; + filelist = filelist->next; + } + assert (filelist == NULL); + + /* Remember the debugging descriptor. */ + files->dbg = dbg; + + /* 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) |