From 681f229a9fbf72ce7882bf81122f1f18bce96c0e Mon Sep 17 00:00:00 2001 From: Nicolas Blanc Date: Wed, 17 Jul 2013 11:44:26 +0200 Subject: [PATCH] Test adding and removing a symbol file at runtime. This test exercises the commands 'add-symbol-file' and 'remove-symbol-file'. 2013-10-29 Nicolas Blanc gdb/testsuite * gdb.base/sym-file-lib.c: New file. * gdb.base/sym-file-loader.c: New file. * gdb.base/sym-file-loader.h: New file. * gdb.base/sym-file-main.c: New file. * gdb.base/sym-file.exp: New file. Signed-off-by: Nicolas Blanc --- gdb/testsuite/gdb.base/sym-file-lib.c | 26 +++ gdb/testsuite/gdb.base/sym-file-loader.c | 353 +++++++++++++++++++++++++++++++ gdb/testsuite/gdb.base/sym-file-loader.h | 99 +++++++++ gdb/testsuite/gdb.base/sym-file-main.c | 79 +++++++ gdb/testsuite/gdb.base/sym-file.exp | 158 ++++++++++++++ 5 files changed, 715 insertions(+) create mode 100644 gdb/testsuite/gdb.base/sym-file-lib.c create mode 100644 gdb/testsuite/gdb.base/sym-file-loader.c create mode 100644 gdb/testsuite/gdb.base/sym-file-loader.h create mode 100644 gdb/testsuite/gdb.base/sym-file-main.c create mode 100644 gdb/testsuite/gdb.base/sym-file.exp diff --git a/gdb/testsuite/gdb.base/sym-file-lib.c b/gdb/testsuite/gdb.base/sym-file-lib.c new file mode 100644 index 0000000..586215d --- /dev/null +++ b/gdb/testsuite/gdb.base/sym-file-lib.c @@ -0,0 +1,26 @@ +/* Copyright 2013 Free Software Foundation, Inc. + This program 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; either version 3 of the License, or + (at your option) any later version. + + This program 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 this program. If not, see . +*/ + +extern int +bar () +{ + return 1; /* gdb break at bar */ +} + +extern int +foo (int a) +{ + return a; /* gdb break at foo */ +} diff --git a/gdb/testsuite/gdb.base/sym-file-loader.c b/gdb/testsuite/gdb.base/sym-file-loader.c new file mode 100644 index 0000000..c55076f --- /dev/null +++ b/gdb/testsuite/gdb.base/sym-file-loader.c @@ -0,0 +1,353 @@ +/* Copyright 2013 Free Software Foundation, Inc. + This program 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; either version 3 of the License, or + (at your option) any later version. + + This program 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 this program. If not, see . +*/ + +#include +#include +#include +#include +#include +#include + +#include "sym-file-loader.h" + +#ifdef TARGET_LP64 + +uint8_t +elf_st_type (uint8_t st_info) +{ + return ELF64_ST_TYPE (st_info); +} + +#elif defined TARGET_ILP32 + +uint8_t +elf_st_type (uint8_t st_info) +{ + return ELF32_ST_TYPE (st_info); +} + +#endif + +/* Load a program segment. */ + +static struct segment * +load (uint8_t *addr, Elf_External_Phdr *phdr, struct segment *tail_seg) +{ + struct segment *seg = NULL; + uint8_t *mapped_addr = NULL; + void *from = NULL; + void *to = NULL; + + /* For the sake of simplicity all operations are permitted. */ + unsigned perm = PROT_READ | PROT_WRITE | PROT_EXEC; + + mapped_addr = (uint8_t *) mmap ((void *) GETADDR (phdr, p_vaddr), + GET (phdr, p_memsz), perm, + MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); + + from = (void *) (addr + GET (phdr, p_offset)); + to = (void *) mapped_addr; + + memcpy (to, from, GET (phdr, p_filesz)); + + seg = (struct segment *) malloc (sizeof (struct segment)); + + if (seg == 0) + return 0; + + seg->mapped_addr = mapped_addr; + seg->phdr = phdr; + seg->next = 0; + + if (tail_seg != 0) + tail_seg->next = seg; + + return seg; +} + +/* Mini shared library loader. No reallocation + is performed for the sake of simplicity. */ + +int +load_shlib (const char *file, Elf_External_Ehdr **ehdr_out, + struct segment **seg_out) +{ + uint64_t i; + int fd; + off_t fsize; + uint8_t *addr; + Elf_External_Ehdr *ehdr; + Elf_External_Phdr *phdr; + struct segment *head_seg = NULL; + struct segment *tail_seg = NULL; + + /* Map the lib in memory for reading. */ + fd = open (file, O_RDONLY); + if (fd < 0) + { + perror ("fopen failed."); + return -1; + } + + fsize = lseek (fd, 0, SEEK_END); + + if (fsize < 0) + { + perror ("lseek failed."); + return -1; + } + + addr = (uint8_t *) mmap (NULL, fsize, PROT_READ, MAP_PRIVATE, fd, 0); + if (addr == (uint8_t *) -1) + { + perror ("mmap failed."); + return -1; + } + + /* Check if the lib is an ELF file. */ + ehdr = (Elf_External_Ehdr *) addr; + if (ehdr->e_ident[EI_MAG0] != ELFMAG0 + || ehdr->e_ident[EI_MAG1] != ELFMAG1 + || ehdr->e_ident[EI_MAG2] != ELFMAG2 + || ehdr->e_ident[EI_MAG3] != ELFMAG3) + { + printf ("Not an ELF file: %x\n", ehdr->e_ident[EI_MAG0]); + return -1; + } + + if (ehdr->e_ident[EI_CLASS] == ELFCLASS32) + { + if (sizeof (void *) != 4) + { + printf ("Architecture mismatch."); + return -1; + } + } + else if (ehdr->e_ident[EI_CLASS] == ELFCLASS64) + { + if (sizeof (void *) != 8) + { + printf ("Architecture mismatch."); + return -1; + } + } + + /* Load the program segments. For the sake of simplicity + assume that no reallocation is needed. */ + phdr = (Elf_External_Phdr *) (addr + GET (ehdr, e_phoff)); + for (i = 0; i < GET (ehdr, e_phnum); i++, phdr++) + { + if (GET (phdr, p_type) == PT_LOAD) + { + struct segment *next_seg = load (addr, phdr, tail_seg); + if (next_seg == 0) + continue; + tail_seg = next_seg; + if (head_seg == 0) + head_seg = next_seg; + } + } + *ehdr_out = ehdr; + *seg_out = head_seg; + return 0; +} + +/* Return the section-header table. */ + +Elf_External_Shdr * +find_shdrtab (Elf_External_Ehdr *ehdr) +{ + return (Elf_External_Shdr *) (((uint8_t *) ehdr) + GET (ehdr, e_shoff)); +} + +/* Return the string table of the section headers. */ + +const char * +find_shstrtab (Elf_External_Ehdr *ehdr, uint64_t *size) +{ + const Elf_External_Shdr *shdr; + const Elf_External_Shdr *shstr; + + if (GET (ehdr, e_shnum) <= GET (ehdr, e_shstrndx)) + { + printf ("The index of the string table is corrupt."); + return NULL; + } + + shdr = find_shdrtab (ehdr); + + shstr = &shdr[GET (ehdr, e_shstrndx)]; + *size = GET (shstr, sh_size); + return ((const char *) ehdr) + GET (shstr, sh_offset); +} + +/* Return the string table named SECTION. */ + +const char * +find_strtab (Elf_External_Ehdr *ehdr, + const char *section, uint64_t *strtab_size) +{ + uint64_t shstrtab_size = 0; + const char *shstrtab; + uint64_t i; + const Elf_External_Shdr *shdr = find_shdrtab (ehdr); + + /* Get the string table of the section headers. */ + shstrtab = find_shstrtab (ehdr, &shstrtab_size); + if (shstrtab == NULL) + return NULL; + + for (i = 0; i < GET (ehdr, e_shnum); i++) + { + uint64_t name = GET (shdr + i, sh_name); + if (GET (shdr + i, sh_type) == SHT_STRTAB && name <= shstrtab_size + && strcmp ((const char *) &shstrtab[name], section) == 0) + { + *strtab_size = GET (shdr + i, sh_size); + return ((const char *) ehdr) + GET (shdr + i, sh_offset); + } + + } + return NULL; +} + +/* Return the section header named SECTION. */ + +Elf_External_Shdr * +find_shdr (Elf_External_Ehdr *ehdr, const char *section) +{ + uint64_t shstrtab_size = 0; + const char *shstrtab; + uint64_t i; + + /* Get the string table of the section headers. */ + shstrtab = find_shstrtab (ehdr, &shstrtab_size); + if (shstrtab == NULL) + return NULL; + + Elf_External_Shdr *shdr = find_shdrtab (ehdr); + for (i = 0; i < GET (ehdr, e_shnum); i++) + { + uint64_t name = GET (shdr + i, sh_name); + if (name <= shstrtab_size) + { + if (strcmp ((const char *) &shstrtab[name], section) == 0) + return &shdr[i]; + } + + } + return NULL; +} + +/* Return the symbol table. */ + +Elf_External_Sym * +find_symtab (Elf_External_Ehdr *ehdr, uint64_t *symtab_size) +{ + uint64_t i; + const Elf_External_Shdr *shdr = find_shdrtab (ehdr); + + for (i = 0; i < GET (ehdr, e_shnum); i++) + { + if (GET (shdr + i, sh_type) == SHT_SYMTAB) + { + *symtab_size = GET (shdr + i, sh_size) / sizeof (Elf_External_Sym); + return (Elf_External_Sym *) (((const char *) ehdr) + + GET (shdr + i, sh_offset)); + } + } + return NULL; +} + +/* Translate a file offset to an address in a loaded segment. */ + +int +translate_offset (uint64_t file_offset, struct segment *seg, void **addr) +{ + while (seg) + { + uint64_t p_from, p_to; + + Elf_External_Phdr *phdr = seg->phdr; + + if (phdr == NULL) + { + seg = seg->next; + continue; + } + + p_from = GET (phdr, p_offset); + p_to = p_from + GET (phdr, p_filesz); + + if (p_from <= file_offset && file_offset < p_to) + { + *addr = (void *) (seg->mapped_addr + (file_offset - p_from)); + return 0; + } + seg = seg->next; + } + + return -1; +} + +/* Lookup the address of FUNC. */ + +int +lookup_function (const char *func, + Elf_External_Ehdr *ehdr, struct segment *seg, void **addr) +{ + const char *strtab; + uint64_t strtab_size = 0; + Elf_External_Sym *symtab; + uint64_t symtab_size = 0; + uint64_t i; + + /* Get the string table for the symbols. */ + strtab = find_strtab (ehdr, ".strtab", &strtab_size); + if (strtab == NULL) + { + printf (".strtab not found."); + return -1; + } + + /* Get the symbol table. */ + symtab = find_symtab (ehdr, &symtab_size); + if (symtab == NULL) + { + printf ("symbol table not found."); + return -1; + } + + for (i = 0; i < symtab_size; i++) + { + Elf_External_Sym *sym = &symtab[i]; + + if (elf_st_type (GET (sym, st_info)) != STT_FUNC) + continue; + + if (GET (sym, st_name) < strtab_size) + { + const char *name = &strtab[GET (sym, st_name)]; + if (strcmp (name, func) == 0) + { + + uint64_t offset = GET (sym, st_value); + return translate_offset (offset, seg, addr); + } + } + } + + return -1; +} diff --git a/gdb/testsuite/gdb.base/sym-file-loader.h b/gdb/testsuite/gdb.base/sym-file-loader.h new file mode 100644 index 0000000..2b21ab2 --- /dev/null +++ b/gdb/testsuite/gdb.base/sym-file-loader.h @@ -0,0 +1,99 @@ +/* Copyright 2013 Free Software Foundation, Inc. + This program 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; either version 3 of the License, or + (at your option) any later version. + + This program 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 this program. If not, see . +*/ + +#ifndef __SYM_FILE_LOADER__ +#define __SYM_FILE_LOADER__ + +#include +#include +#include +#include + +#ifdef TARGET_LP64 + +typedef Elf64_External_Phdr Elf_External_Phdr; +typedef Elf64_External_Ehdr Elf_External_Ehdr; +typedef Elf64_External_Shdr Elf_External_Shdr; +typedef Elf64_External_Sym Elf_External_Sym; +typedef uint64_t Elf_Addr; + +#elif defined TARGET_ILP32 + +typedef Elf32_External_Phdr Elf_External_Phdr; +typedef Elf32_External_Ehdr Elf_External_Ehdr; +typedef Elf32_External_Shdr Elf_External_Shdr; +typedef Elf32_External_Sym Elf_External_Sym; +typedef uint32_t Elf_Addr; + +#endif + +#define GET(hdr, field) (\ +sizeof ((hdr)->field) == 1 ? (uint64_t) (hdr)->field[0] : \ +sizeof ((hdr)->field) == 2 ? (uint64_t) *(uint16_t *) (hdr)->field : \ +sizeof ((hdr)->field) == 4 ? (uint64_t) *(uint32_t *) (hdr)->field : \ +sizeof ((hdr)->field) == 8 ? *(uint64_t *) (hdr)->field : \ +*(uint64_t *) NULL) + +#define GETADDR(hdr, field) (\ +sizeof ((hdr)->field) == sizeof (Elf_Addr) ? *(Elf_Addr *) (hdr)->field : \ +*(Elf_Addr *) NULL) + +struct segment +{ + uint8_t *mapped_addr; + Elf_External_Phdr *phdr; + struct segment *next; +}; + +/* Mini shared library loader. No reallocation is performed + for the sake of simplicity. */ + +int +load_shlib (const char *file, Elf_External_Ehdr **ehdr_out, + struct segment **seg_out); + +/* Return the section-header table. */ + +Elf_External_Shdr *find_shdrtab (Elf_External_Ehdr *ehdr); + +/* Return the string table of the section headers. */ + +const char *find_shstrtab (Elf_External_Ehdr *ehdr, uint64_t *size); + +/* Return the string table named SECTION. */ + +const char *find_strtab (Elf_External_Ehdr *ehdr, + const char *section, uint64_t *strtab_size); + +/* Return the section header named SECTION. */ + +Elf_External_Shdr *find_shdr (Elf_External_Ehdr *ehdr, const char *section); + +/* Return the symbol table. */ + +Elf_External_Sym *find_symtab (Elf_External_Ehdr *ehdr, + uint64_t *symtab_size); + +/* Translate a file offset to an address in a loaded segment. */ + +int translate_offset (uint64_t file_offset, struct segment *seg, void **addr); + +/* Lookup the address of FUNC. */ + +int +lookup_function (const char *func, Elf_External_Ehdr* ehdr, + struct segment *seg, void **addr); + +#endif diff --git a/gdb/testsuite/gdb.base/sym-file-main.c b/gdb/testsuite/gdb.base/sym-file-main.c new file mode 100644 index 0000000..932ed0d --- /dev/null +++ b/gdb/testsuite/gdb.base/sym-file-main.c @@ -0,0 +1,79 @@ +/* Copyright 2013 Free Software Foundation, Inc. + This program 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; either version 3 of the License, or + (at your option) any later version. + + This program 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 this program. If not, see . +*/ + +#include +#include + +#include "sym-file-loader.h" + +void +gdb_add_symbol_file (void *addr, const char *file) +{ + return; +} + +void +gdb_remove_symbol_file (void *addr) +{ + return; +} + +/* Load a shared library without relying on the standard + loader to test GDB's commands for adding and removing + symbol files at runtime. */ + +int +main (int argc, const char *argv[]) +{ + const char *file = SHLIB_NAME; + Elf_External_Ehdr *ehdr = NULL; + struct segment *head_seg = NULL; + Elf_External_Shdr *text; + char *text_addr = NULL; + int (*pbar) () = NULL; + int (*pfoo) (int) = NULL; + + if (load_shlib (file, &ehdr, &head_seg) != 0) + return -1; + + /* Get the text section. */ + text = find_shdr (ehdr, ".text"); + if (text == NULL) + return -1; + + /* Notify GDB to add the symbol file. */ + if (translate_offset (GET (text, sh_offset), head_seg, (void **) &text_addr) + != 0) + return -1; + + gdb_add_symbol_file (text_addr, file); + + /* Call bar from SHLIB_NAME. */ + if (lookup_function ("bar", ehdr, head_seg, (void *) &pbar) != 0) + return -1; + + (*pbar) (); + + /* Call foo from SHLIB_NAME. */ + if (lookup_function ("foo", ehdr, head_seg, (void *) &pfoo) != 0) + return -1; + + (*pfoo) (2); + + /* Notify GDB to remove the symbol file. */ + gdb_remove_symbol_file (text_addr); + + return 0; +} diff --git a/gdb/testsuite/gdb.base/sym-file.exp b/gdb/testsuite/gdb.base/sym-file.exp new file mode 100644 index 0000000..6af861b --- /dev/null +++ b/gdb/testsuite/gdb.base/sym-file.exp @@ -0,0 +1,158 @@ +# Copyright 2013 Free Software Foundation, Inc. + +# This program 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; either version 3 of the License, or +# (at your option) any later version. +# +# This program 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 this program. If not, see . */ + +# Test adding and removing a symbol file dynamically: +# 1) Run to gdb_add_symbol_file in $srcfile. +# 2) Set a pending breakpoint at bar in $srcfile3. +# 3) Load $shlib_name using 'add-symbol-file'. +# 4) 'info files' must display ${lib_basename}. +# 5) Continue to bar in $srcfile3. +# 6) Set a breakpoint at foo in $srcfile3. +# 7) Continue to foo in $srcfile3. +# 8) Set a breakpoint at gdb_remove_symbol_file. +# 9) Continue to gdb_remove_symbol_file in $srcfile. +# 10) Remove $shlib_name using 'remove-symbol-file'. +# 11) 'info files' must not display ${lib_basename}, anymore. +# 12) Check that the breakpoints at foo and bar are pending. +# 13) Check that the execution can continue without error. + +if {![is_elf_target]} { + return 0 +} + +if [skip_shlib_tests] { + return 0 +} + +if [is_remote target] { + return 0 +} + +set target_size TARGET_UNKNOWN +if {[is_lp64_target]} { + set target_size TARGET_LP64 +} elseif {[is_ilp32_target]} { + set target_size TARGET_ILP32 +} else { + return 0 +} + +set main_basename sym-file-main +set loader_basename sym-file-loader +set lib_basename sym-file-lib + +standard_testfile $main_basename.c $loader_basename.c $lib_basename.c + +set libsrc "${srcdir}/${subdir}/${srcfile3}" +set shlib_name [standard_output_file ${lib_basename}.so] +set exec_opts [list debug "additional_flags= -I$srcdir/../../include/ -D$target_size\ + -DSHLIB_NAME\\=\"$shlib_name\""] + +if [get_compiler_info] { + return -1 +} + +if {[gdb_compile_shlib $libsrc $shlib_name {debug}] != ""} { + untested ${testfile} + return +} + +if {[prepare_for_testing $testfile $binfile "$srcfile $srcfile2" $exec_opts]} { + return +} + +# 1) Run to GDB_ADD_SYMBOl_FILE in $srcfile for adding +# $shlib_name. +set result [runto gdb_add_symbol_file] +if {!$result} then { + return +} + +# 2) Set a pending breakpoint at bar in $srcfile3. +set result [gdb_breakpoint bar allow-pending] +if {!$result} then { + return +} + +# 3) Add $shlib_name using 'add-symbol-file'. +set result [gdb_test "add-symbol-file ${shlib_name} addr" \ + "Reading symbols from .*${lib_basename}\\.so\\.\\.\\.done\\." \ + "add-symbol-file .*${lib_basename}\\.so addr" \ + "add symbol table from file \".*${lib_basename}\\.so\"\ + at.*\\(y or n\\) " \ + "y"] +if {$result != 0} then { + return +} + +# 4) 'info files' must display $srcfile3. +gdb_test "info files" \ + "^(?=(.*${lib_basename})).*" \ + "info files must display ${lib_basename}" + +# 5) Continue to bar in $srcfile3 to ensure that the breakpoint +# was bound correctly after adding $shilb_name. +set lnum_bar [gdb_get_line_number "break at bar" $srcfile3] +gdb_continue_to_breakpoint bar ".*${lib_basename}\\.c:$lnum_bar.*" + +# 6) Set a breakpoint at foo in $srcfile3. +set result [gdb_breakpoint foo] +if {!$result} then { + return +} + +# 7) Continue to foo in $srcfile3 to ensure that the breakpoint +# was bound correctly. +set lnum_foo [gdb_get_line_number "break at foo" $srcfile3] +gdb_continue_to_breakpoint foo ".*${lib_basename}\\.c:$lnum_foo.*" + +# 8) Set a breakpoint at gdb_remove_symbol_file in $srcfile for +# removing $shlib_name. +set result [gdb_breakpoint gdb_remove_symbol_file] +if {!$result} then { + return +} + +# 9) Continue to gdb_remove_symbol_file in $srcfile. +gdb_continue_to_breakpoint gdb_remove_symbol_file + +# 10) Remove $shlib_name using 'remove-symbol-file'. +set result [gdb_test "remove-symbol-file -a addr" \ + ""\ + "remove-symbol-file -a addr" \ + "Remove symbol table from file \".*${lib_basename}\\.so\"\\?\ +.*\\(y or n\\) " \ + "y"] +if {$result != 0} then { + return +} + +# 11) 'info files' must not display ${lib_basename}, anymore. +gdb_test "info files" \ + "^(?!(.*${lib_basename})).*" \ + "info files must not display ${lib_basename}" + +# 12) Check that the breakpoints at foo and bar are pending after removing +# $shlib_name. +gdb_test "info breakpoints 2" \ + ".*PENDING.*" \ + "check if Breakpoint 2 is pending." + +gdb_test "info breakpoints 3" \ + ".*PENDING.*" \ + "check if Breakpoint 3 is pending." + +# 13) Check that the execution can continue without error. +gdb_continue_to_end -- 2.7.4