/* Auxiliary vector support for GDB, the GNU debugger. Copyright 2004 Free Software Foundation, Inc. This file is part of GDB. 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 2 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, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #include "defs.h" #include "target.h" #include "gdbtypes.h" #include "command.h" #include "inferior.h" #include "valprint.h" #include "gdb_assert.h" #include "auxv.h" #include "elf/common.h" #include #include /* This function is called like a to_xfer_partial hook, but must be called with TARGET_OBJECT_AUXV. It handles access via /proc/PID/auxv, which is the common method. This function is appropriate for doing: #define NATIVE_XFER_AUXV procfs_xfer_auxv for a native target that uses inftarg.c's child_xfer_partial hook. */ LONGEST procfs_xfer_auxv (struct target_ops *ops, int /* enum target_object */ object, const char *annex, void *readbuf, const void *writebuf, ULONGEST offset, LONGEST len) { char *pathname; int fd; LONGEST n; gdb_assert (object == TARGET_OBJECT_AUXV); gdb_assert (readbuf || writebuf); pathname = xstrprintf ("/proc/%d/auxv", PIDGET (inferior_ptid)); fd = open (pathname, writebuf != NULL ? O_WRONLY : O_RDONLY); xfree (pathname); if (fd < 0) return -1; if (offset != (ULONGEST) 0 && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset) n = -1; else if (readbuf != NULL) n = read (fd, readbuf, len); else n = write (fd, writebuf, len); (void) close (fd); return n; } /* Read all the auxv data into a contiguous xmalloc'd buffer, stored in *DATA. Return the size in bytes of this data. If zero, there is no data and *DATA is null. if < 0, there was an error and *DATA is null. */ LONGEST target_auxv_read (struct target_ops *ops, char **data) { size_t auxv_alloc = 512, auxv_pos = 0; char *auxv = xmalloc (auxv_alloc); int n; while (1) { n = target_read_partial (ops, TARGET_OBJECT_AUXV, NULL, &auxv[auxv_pos], 0, auxv_alloc - auxv_pos); if (n <= 0) break; auxv_pos += n; if (auxv_pos < auxv_alloc) /* Read all there was. */ break; gdb_assert (auxv_pos == auxv_alloc); auxv_alloc *= 2; auxv = xrealloc (auxv, auxv_alloc); } if (auxv_pos == 0) { xfree (auxv); *data = NULL; return n; } *data = auxv; return auxv_pos; } /* Read one auxv entry from *READPTR, not reading locations >= ENDPTR. Return 0 if *READPTR is already at the end of the buffer. Return -1 if there is insufficient buffer for a whole entry. Return 1 if an entry was read into *TYPEP and *VALP. */ int target_auxv_parse (struct target_ops *ops, char **readptr, char *endptr, CORE_ADDR *typep, CORE_ADDR *valp) { const int sizeof_auxv_field = TYPE_LENGTH (builtin_type_void_data_ptr); char *ptr = *readptr; if (endptr == ptr) return 0; if (endptr - ptr < sizeof_auxv_field * 2) return -1; *typep = extract_unsigned_integer (ptr, sizeof_auxv_field); ptr += sizeof_auxv_field; *valp = extract_unsigned_integer (ptr, sizeof_auxv_field); ptr += sizeof_auxv_field; *readptr = ptr; return 1; } /* Extract the auxiliary vector entry with a_type matching MATCH. Return zero if no such entry was found, or -1 if there was an error getting the information. On success, return 1 after storing the entry's value field in *VALP. */ int target_auxv_search (struct target_ops *ops, CORE_ADDR match, CORE_ADDR *valp) { CORE_ADDR type, val; char *data; int n = target_auxv_read (ops, &data); char *ptr = data; int ents = 0; if (n <= 0) return n; while (1) switch (target_auxv_parse (ops, &ptr, data + n, &type, &val)) { case 1: /* Here's an entry, check it. */ if (type == match) { xfree (data); *valp = val; return 1; } break; case 0: /* End of the vector. */ xfree (data); return 0; default: /* Bogosity. */ xfree (data); return -1; } /*NOTREACHED*/ } /* Print the contents of the target's AUXV on the specified file. */ int fprint_target_auxv (struct ui_file *file, struct target_ops *ops) { CORE_ADDR type, val; char *data; int len = target_auxv_read (ops, &data); char *ptr = data; int ents = 0; if (len <= 0) return len; while (target_auxv_parse (ops, &ptr, data + len, &type, &val) > 0) { extern int addressprint; const char *name = "???"; const char *description = ""; enum { dec, hex, str } flavor = hex; switch (type) { #define TAG(tag, text, kind) \ case tag: name = #tag; description = text; flavor = kind; break TAG (AT_NULL, "End of vector", hex); TAG (AT_IGNORE, "Entry should be ignored", hex); TAG (AT_EXECFD, "File descriptor of program", dec); TAG (AT_PHDR, "Program headers for program", hex); TAG (AT_PHENT, "Size of program header entry", dec); TAG (AT_PHNUM, "Number of program headers", dec); TAG (AT_PAGESZ, "System page size", dec); TAG (AT_BASE, "Base address of interpreter", hex); TAG (AT_FLAGS, "Flags", hex); TAG (AT_ENTRY, "Entry point of program", hex); TAG (AT_NOTELF, "Program is not ELF", dec); TAG (AT_UID, "Real user ID", dec); TAG (AT_EUID, "Effective user ID", dec); TAG (AT_GID, "Real group ID", dec); TAG (AT_EGID, "Effective group ID", dec); TAG (AT_CLKTCK, "Frequency of times()", dec); TAG (AT_PLATFORM, "String identifying platform", str); TAG (AT_HWCAP, "Machine-dependent CPU capability hints", hex); TAG (AT_FPUCW, "Used FPU control word", dec); TAG (AT_DCACHEBSIZE, "Data cache block size", dec); TAG (AT_ICACHEBSIZE, "Instruction cache block size", dec); TAG (AT_UCACHEBSIZE, "Unified cache block size", dec); TAG (AT_IGNOREPPC, "Entry should be ignored", dec); TAG (AT_SYSINFO, "Special system info/entry points", hex); TAG (AT_SYSINFO_EHDR, "System-supplied DSO's ELF header", hex); TAG (AT_SECURE, "Boolean, was exec setuid-like?", dec); TAG (AT_SUN_UID, "Effective user ID", dec); TAG (AT_SUN_RUID, "Real user ID", dec); TAG (AT_SUN_GID, "Effective group ID", dec); TAG (AT_SUN_RGID, "Real group ID", dec); TAG (AT_SUN_LDELF, "Dynamic linker's ELF header", hex); TAG (AT_SUN_LDSHDR, "Dynamic linker's section headers", hex); TAG (AT_SUN_LDNAME, "String giving name of dynamic linker", str); TAG (AT_SUN_LPAGESZ, "Large pagesize", dec); TAG (AT_SUN_PLATFORM, "Platform name string", str); TAG (AT_SUN_HWCAP, "Machine-dependent CPU capability hints", hex); TAG (AT_SUN_IFLUSH, "Should flush icache?", dec); TAG (AT_SUN_CPU, "CPU name string", str); TAG (AT_SUN_EMUL_ENTRY, "COFF entry point address", hex); TAG (AT_SUN_EMUL_EXECFD, "COFF executable file descriptor", dec); TAG (AT_SUN_EXECNAME, "Canonicalized file name given to execve", str); TAG (AT_SUN_MMU, "String for name of MMU module", str); TAG (AT_SUN_LDDATA, "Dynamic linker's data segment address", hex); } fprintf_filtered (file, "%-4s %-20s %-30s ", paddr_d (type), name, description); switch (flavor) { case dec: fprintf_filtered (file, "%s\n", paddr_d (val)); break; case hex: fprintf_filtered (file, "0x%s\n", paddr_nz (val)); break; case str: if (addressprint) fprintf_filtered (file, "0x%s", paddr_nz (val)); val_print_string (val, -1, 1, file); fprintf_filtered (file, "\n"); break; } ++ents; } xfree (data); return ents; } static void info_auxv_command (char *cmd, int from_tty) { if (! target_has_stack) error ("The program has no auxiliary information now."); else { int ents = fprint_target_auxv (gdb_stdout, ¤t_target); if (ents < 0) error ("No auxiliary vector found, or failed reading it."); else if (ents == 0) error ("Auxiliary vector is empty."); } } extern initialize_file_ftype _initialize_auxv; /* -Wmissing-prototypes; */ void _initialize_auxv (void) { add_info ("auxv", info_auxv_command, "Display the inferior's auxiliary vector.\n\ This is information provided by the operating system at program startup."); }