[PATCH 2/2] Testsuite for varobj updation after symbol removal

Taimoor Mirza
2014-06-27T10:14:27Z

This patch provides testcases for variable object updation after removing
symbols. Test programs are same as used for testing remove-symbol-file
command in gdb.base. sym-file-main.c is modified to just add a global
variable for which varible object is created in testsuite.

Testing:
=======
This is tested for x86 target and also on ppc-linux-gnu and mips-gnu-linux
using both simulator and real boards.

2014-06-27 Taimoor Mirza <tmirza@codesourcery.com>

* gdb.mi/mi-var-invalidate.exp: Add tests to check global
variable object change list is correct when its value is
updated before removing symbols.
* gdb.mi/sym-file-loader.c: New file.
* gdb.mi/sym-file-loader.h: New file.
* gdb.mi/sym-file-main.c: New file.
* gdb.mi/sym-file-lib.c: New file.

---
gdb/testsuite/gdb.mi/mi-var-invalidate.exp | 67 ++++++
gdb/testsuite/gdb.mi/sym-file-lib.c | 26 ++
gdb/testsuite/gdb.mi/sym-file-loader.c | 353 ++++++++++++++++++++++++++++
gdb/testsuite/gdb.mi/sym-file-loader.h | 99 ++++++++
gdb/testsuite/gdb.mi/sym-file-main.c | 84 +++++++
5 files changed, 629 insertions(+)
create mode 100644 gdb/testsuite/gdb.mi/sym-file-lib.c
create mode 100644 gdb/testsuite/gdb.mi/sym-file-loader.c
create mode 100644 gdb/testsuite/gdb.mi/sym-file-loader.h
create mode 100644 gdb/testsuite/gdb.mi/sym-file-main.c

diff --git a/gdb/testsuite/gdb.mi/mi-var-invalidate.exp b/gdb/testsuite/gdb.mi/mi-var-invalidate.exp
index e6ba392..e3bf953 100644
--- a/gdb/testsuite/gdb.mi/mi-var-invalidate.exp
+++ b/gdb/testsuite/gdb.mi/mi-var-invalidate.exp
@@ -121,5 +121,72 @@ mi_gdb_test "-var-info-type global_simple" \
"\\^done,type=\"\"" \
"no type for invalid variable global_simple"

+# Test varobj updation after removing symbols.
+
+if {[skip_shlib_tests]} {
+ 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 test_bin_name "sym-test-file"
+set test_bin [standard_output_file ${test_bin_name}]
+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 -1
+}
+
+if {[build_executable $testfile $test_bin "$srcfile $srcfile2" $exec_opts]} {
+ return -1
+}
+
+mi_delete_breakpoints
+mi_gdb_load ${test_bin}
+
+# Create varobj for count variable.
+mi_create_varobj var_count count "Create global varobj for count"
+
+# Run to GDB_ADD_SYMBOl_FILE in $srcfile for adding
+# $shlib_name.
+mi_runto gdb_add_symbol_file
+
+# Add $shlib_name using 'add-symbol-file'.
+mi_gdb_test "-interpreter-exec console \"add-symbol-file ${shlib_name} addr\"" \
+ "~\"add symbol table from file .*so.*at.*= $hex.*\\^done" \
+ "add-symbol-file ${shlib_name}"
+
+# Continue to gdb_remove_symbol_file in $srcfile.
+mi_runto gdb_remove_symbol_file
+
+# Remove $shlib_name using 'remove-symbol-file'.
+mi_gdb_test "-interpreter-exec console \"remove-symbol-file -a addr\"" \
+ ".*\\^done"\
+ "remove-symbol-file test"
+
+# Check var_count varobj changelist is not empty.
+mi_varobj_update var_count {var_count} "Update var_count"
+
mi_gdb_exit
return 0
diff --git a/gdb/testsuite/gdb.mi/sym-file-lib.c b/gdb/testsuite/gdb.mi/sym-file-lib.c
new file mode 100644
index 0000000..dae5188
--- /dev/null
+++ b/gdb/testsuite/gdb.mi/sym-file-lib.c
@@ -0,0 +1,26 @@
+/* Copyright 2013-2014 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 <http://www.gnu.org/licenses/>.
+*/
+
+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.mi/sym-file-loader.c b/gdb/testsuite/gdb.mi/sym-file-loader.c
new file mode 100644
index 0000000..c72a1d1
--- /dev/null
+++ b/gdb/testsuite/gdb.mi/sym-file-loader.c
@@ -0,0 +1,353 @@
+/* Copyright 2013-2014 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 <http://www.gnu.org/licenses/>.
+*/
+
+#include <unistd.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mman.h>
+
+#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.mi/sym-file-loader.h b/gdb/testsuite/gdb.mi/sym-file-loader.h
new file mode 100644
index 0000000..03dc7e1
--- /dev/null
+++ b/gdb/testsuite/gdb.mi/sym-file-loader.h
@@ -0,0 +1,99 @@
+/* Copyright 2013-2014 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 <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef __SYM_FILE_LOADER__
+#define __SYM_FILE_LOADER__
+
+#include <inttypes.h>
+#include <ansidecl.h>
+#include <elf/common.h>
+#include <elf/external.h>
+
+#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.mi/sym-file-main.c b/gdb/testsuite/gdb.mi/sym-file-main.c
new file mode 100644
index 0000000..8260824
--- /dev/null
+++ b/gdb/testsuite/gdb.mi/sym-file-main.c
@@ -0,0 +1,84 @@
+/* Copyright 2013-2014 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 <http://www.gnu.org/licenses/>.
+*/
+
+#include <stdlib.h>
+#include <stdio.h>
+
+#include "sym-file-loader.h"
+
+// Global variable
+int count = 0;
+
+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);
+
+ count++;
+
+ /* Notify GDB to remove the symbol file. */
+ gdb_remove_symbol_file (text_addr);
+
+ return 0;
+}
--
1.7.9.5