| /*--------------------------------------------------------------------*/ |
| /*--- Management of symbols and debugging information. ---*/ |
| /*--- vg_symtab2.c ---*/ |
| /*--------------------------------------------------------------------*/ |
| |
| /* |
| This file is part of Valgrind, an x86 protected-mode emulator |
| designed for debugging and profiling binaries on x86-Unixes. |
| |
| Copyright (C) 2000-2002 Julian Seward |
| jseward@acm.org |
| |
| 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. |
| |
| The GNU General Public License is contained in the file LICENSE. |
| */ |
| |
| #include "vg_include.h" |
| #include "vg_unsafe.h" |
| |
| #include <elf.h> /* ELF defns */ |
| #include <a.out.h> /* stabs defns */ |
| |
| |
| /* Majorly rewritten Sun 3 Feb 02 to enable loading symbols from |
| dlopen()ed libraries, which is something that KDE3 does a lot. |
| Still kludgey, though less than before: |
| |
| * we don't check whether we should throw away some symbol tables |
| when munmap() happens |
| |
| * symbol table reading code for ELF binaries is a shambles. |
| Use GHC's fptools/ghc/rts/Linker.c as the basis for something better. |
| */ |
| |
| /*------------------------------------------------------------*/ |
| /*--- Structs n stuff ---*/ |
| /*------------------------------------------------------------*/ |
| |
| /* Stabs entry types, from: |
| * The "stabs" debug format |
| * Menapace, Kingdon and MacKenzie |
| * Cygnus Support |
| */ |
| typedef enum { N_GSYM = 32, /* Global symbol */ |
| N_FUN = 36, /* Function start or end */ |
| N_STSYM = 38, /* Data segment file-scope variable */ |
| N_LCSYM = 40, /* BSS segment file-scope variable */ |
| N_RSYM = 64, /* Register variable */ |
| N_SLINE = 68, /* Source line number */ |
| N_SO = 100, /* Source file path and name */ |
| N_LSYM = 128, /* Stack variable or type */ |
| N_SOL = 132, /* Include file name */ |
| N_LBRAC = 192, /* Start of lexical block */ |
| N_RBRAC = 224 /* End of lexical block */ |
| } stab_types; |
| |
| /* A structure to hold an ELF symbol (very crudely). */ |
| typedef |
| struct { |
| Addr addr; /* lowest address of entity */ |
| UInt size; /* size in bytes */ |
| Int nmoff; /* offset of name in this SegInfo's str tab */ |
| } |
| RiSym; |
| |
| /* Line count at which overflow happens, due to line numbers being stored as |
| * shorts in `struct nlist' in a.out.h. */ |
| #define LINENO_OVERFLOW (1 << (sizeof(short) * 8)) |
| |
| #define LINENO_BITS 20 |
| #define LOC_SIZE_BITS (32 - LINENO_BITS) |
| #define MAX_LINENO (1 << LINENO_BITS) |
| |
| /* Unlikely to have any lines with instruction ranges > 4096 bytes */ |
| #define MAX_LOC_SIZE (1 << LOC_SIZE_BITS) |
| |
| /* Number used to detect line number overflows; if one line is 60000-odd |
| * smaller than the previous, is was probably an overflow. |
| */ |
| #define OVERFLOW_DIFFERENCE (LINENO_OVERFLOW - 5000) |
| |
| /* A structure to hold addr-to-source info for a single line. There can be a |
| * lot of these, hence the dense packing. */ |
| typedef |
| struct { |
| /* Word 1 */ |
| Addr addr; /* lowest address for this line */ |
| /* Word 2 */ |
| UShort size:LOC_SIZE_BITS; /* byte size; we catch overflows of this */ |
| UInt lineno:LINENO_BITS; /* source line number, or zero */ |
| /* Word 3 */ |
| UInt fnmoff; /* source filename; offset in this |
| SegInfo's str tab */ |
| } |
| RiLoc; |
| |
| |
| /* A structure which contains information pertaining to one mapped |
| text segment. */ |
| typedef |
| struct _SegInfo { |
| struct _SegInfo* next; |
| /* Description of the mapped segment. */ |
| Addr start; |
| UInt size; |
| UChar* filename; /* in mallocville */ |
| UInt foffset; |
| /* An expandable array of symbols. */ |
| RiSym* symtab; |
| UInt symtab_used; |
| UInt symtab_size; |
| /* An expandable array of locations. */ |
| RiLoc* loctab; |
| UInt loctab_used; |
| UInt loctab_size; |
| /* An expandable array of characters -- the string table. */ |
| Char* strtab; |
| UInt strtab_used; |
| UInt strtab_size; |
| /* offset is what we need to add to symbol table entries |
| to get the real location of that symbol in memory. |
| For executables, offset is zero. |
| For .so's, offset == base_addr. |
| This seems like a giant kludge to me. |
| */ |
| UInt offset; |
| } |
| SegInfo; |
| |
| |
| /* -- debug helper -- */ |
| static void ppSegInfo ( SegInfo* si ) |
| { |
| VG_(printf)("name: %s\n" |
| "start %p, size %d, foffset %d\n", |
| si->filename?si->filename : (UChar*)"NULL", |
| si->start, si->size, si->foffset ); |
| } |
| |
| static void freeSegInfo ( SegInfo* si ) |
| { |
| vg_assert(si != NULL); |
| if (si->filename) VG_(free)(VG_AR_SYMTAB, si->filename); |
| if (si->symtab) VG_(free)(VG_AR_SYMTAB, si->symtab); |
| if (si->loctab) VG_(free)(VG_AR_SYMTAB, si->loctab); |
| if (si->strtab) VG_(free)(VG_AR_SYMTAB, si->strtab); |
| VG_(free)(VG_AR_SYMTAB, si); |
| } |
| |
| |
| /*------------------------------------------------------------*/ |
| /*--- Adding stuff ---*/ |
| /*------------------------------------------------------------*/ |
| |
| /* Add a str to the string table, including terminating zero, and |
| return offset of the string in vg_strtab. */ |
| |
| static __inline__ |
| Int addStr ( SegInfo* si, Char* str ) |
| { |
| Char* new_tab; |
| Int new_sz, i, space_needed; |
| |
| space_needed = 1 + VG_(strlen)(str); |
| if (si->strtab_used + space_needed > si->strtab_size) { |
| new_sz = 2 * si->strtab_size; |
| if (new_sz == 0) new_sz = 5000; |
| new_tab = VG_(malloc)(VG_AR_SYMTAB, new_sz); |
| if (si->strtab != NULL) { |
| for (i = 0; i < si->strtab_used; i++) |
| new_tab[i] = si->strtab[i]; |
| VG_(free)(VG_AR_SYMTAB, si->strtab); |
| } |
| si->strtab = new_tab; |
| si->strtab_size = new_sz; |
| } |
| |
| for (i = 0; i < space_needed; i++) |
| si->strtab[si->strtab_used+i] = str[i]; |
| |
| si->strtab_used += space_needed; |
| vg_assert(si->strtab_used <= si->strtab_size); |
| return si->strtab_used - space_needed; |
| } |
| |
| /* Add a symbol to the symbol table. */ |
| |
| static __inline__ |
| void addSym ( SegInfo* si, RiSym* sym ) |
| { |
| Int new_sz, i; |
| RiSym* new_tab; |
| |
| /* Ignore zero-sized syms. */ |
| if (sym->size == 0) return; |
| |
| if (si->symtab_used == si->symtab_size) { |
| new_sz = 2 * si->symtab_size; |
| if (new_sz == 0) new_sz = 500; |
| new_tab = VG_(malloc)(VG_AR_SYMTAB, new_sz * sizeof(RiSym) ); |
| if (si->symtab != NULL) { |
| for (i = 0; i < si->symtab_used; i++) |
| new_tab[i] = si->symtab[i]; |
| VG_(free)(VG_AR_SYMTAB, si->symtab); |
| } |
| si->symtab = new_tab; |
| si->symtab_size = new_sz; |
| } |
| |
| si->symtab[si->symtab_used] = *sym; |
| si->symtab_used++; |
| vg_assert(si->symtab_used <= si->symtab_size); |
| } |
| |
| /* Add a location to the location table. */ |
| |
| static __inline__ |
| void addLoc ( SegInfo* si, RiLoc* loc ) |
| { |
| Int new_sz, i; |
| RiLoc* new_tab; |
| |
| /* Zero-sized locs should have been ignored earlier */ |
| vg_assert(loc->size > 0); |
| |
| if (si->loctab_used == si->loctab_size) { |
| new_sz = 2 * si->loctab_size; |
| if (new_sz == 0) new_sz = 500; |
| new_tab = VG_(malloc)(VG_AR_SYMTAB, new_sz * sizeof(RiLoc) ); |
| if (si->loctab != NULL) { |
| for (i = 0; i < si->loctab_used; i++) |
| new_tab[i] = si->loctab[i]; |
| VG_(free)(VG_AR_SYMTAB, si->loctab); |
| } |
| si->loctab = new_tab; |
| si->loctab_size = new_sz; |
| } |
| |
| si->loctab[si->loctab_used] = *loc; |
| si->loctab_used++; |
| vg_assert(si->loctab_used <= si->loctab_size); |
| } |
| |
| |
| |
| /*------------------------------------------------------------*/ |
| /*--- Helpers ---*/ |
| /*------------------------------------------------------------*/ |
| |
| /* Non-fatal -- use vg_panic if terminal. */ |
| static |
| void vg_symerr ( Char* msg ) |
| { |
| if (VG_(clo_verbosity) > 1) |
| VG_(message)(Vg_UserMsg,"%s", msg ); |
| } |
| |
| |
| /* Print a symbol. */ |
| static |
| void printSym ( SegInfo* si, Int i ) |
| { |
| VG_(printf)( "%5d: %8p .. %8p (%d) %s\n", |
| i, |
| si->symtab[i].addr, |
| si->symtab[i].addr + si->symtab[i].size - 1, si->symtab[i].size, |
| &si->strtab[si->symtab[i].nmoff] ); |
| } |
| |
| |
| #if 0 |
| /* Print the entire sym tab. */ |
| static __attribute__ ((unused)) |
| void printSymtab ( void ) |
| { |
| Int i; |
| VG_(printf)("\n------ BEGIN vg_symtab ------\n"); |
| for (i = 0; i < vg_symtab_used; i++) |
| printSym(i); |
| VG_(printf)("------ BEGIN vg_symtab ------\n"); |
| } |
| #endif |
| |
| #if 0 |
| /* Paranoid strcat. */ |
| static |
| void safeCopy ( UChar* dst, UInt maxlen, UChar* src ) |
| { |
| UInt i = 0, j = 0; |
| while (True) { |
| if (i >= maxlen) return; |
| if (dst[i] == 0) break; |
| i++; |
| } |
| while (True) { |
| if (i >= maxlen) return; |
| dst[i] = src[j]; |
| if (src[j] == 0) return; |
| i++; j++; |
| } |
| } |
| #endif |
| |
| /*------------------------------------------------------------*/ |
| /*--- Canonicalisers ---*/ |
| /*------------------------------------------------------------*/ |
| |
| /* Sort the symtab by starting address, and emit warnings if any |
| symbols have overlapping address ranges. We use that old chestnut, |
| shellsort. Mash the table around so as to establish the property |
| that addresses are in order and the ranges to not overlap. This |
| facilitates using binary search to map addresses to symbols when we |
| come to query the table. |
| */ |
| static |
| void canonicaliseSymtab ( SegInfo* si ) |
| { |
| /* Magic numbers due to Janet Incerpi and Robert Sedgewick. */ |
| Int incs[16] = { 1, 3, 7, 21, 48, 112, 336, 861, 1968, |
| 4592, 13776, 33936, 86961, 198768, |
| 463792, 1391376 }; |
| Int lo = 0; |
| Int hi = si->symtab_used-1; |
| Int i, j, h, bigN, hp, n_merged, n_truncated; |
| RiSym v; |
| Addr s1, s2, e1, e2; |
| |
| # define SWAP(ty,aa,bb) \ |
| do { ty tt = (aa); (aa) = (bb); (bb) = tt; } while (0) |
| |
| bigN = hi - lo + 1; if (bigN < 2) return; |
| hp = 0; while (hp < 16 && incs[hp] < bigN) hp++; hp--; |
| vg_assert(0 <= hp && hp < 16); |
| |
| for (; hp >= 0; hp--) { |
| h = incs[hp]; |
| i = lo + h; |
| while (1) { |
| if (i > hi) break; |
| v = si->symtab[i]; |
| j = i; |
| while (si->symtab[j-h].addr > v.addr) { |
| si->symtab[j] = si->symtab[j-h]; |
| j = j - h; |
| if (j <= (lo + h - 1)) break; |
| } |
| si->symtab[j] = v; |
| i++; |
| } |
| } |
| |
| cleanup_more: |
| |
| /* If two symbols have identical address ranges, favour the |
| one with the longer name. |
| */ |
| do { |
| n_merged = 0; |
| j = si->symtab_used; |
| si->symtab_used = 0; |
| for (i = 0; i < j; i++) { |
| if (i < j-1 |
| && si->symtab[i].addr == si->symtab[i+1].addr |
| && si->symtab[i].size == si->symtab[i+1].size) { |
| n_merged++; |
| /* merge the two into one */ |
| if (VG_(strlen)(&si->strtab[si->symtab[i].nmoff]) |
| > VG_(strlen)(&si->strtab[si->symtab[i+1].nmoff])) { |
| si->symtab[si->symtab_used++] = si->symtab[i]; |
| } else { |
| si->symtab[si->symtab_used++] = si->symtab[i+1]; |
| } |
| i++; |
| } else { |
| si->symtab[si->symtab_used++] = si->symtab[i]; |
| } |
| } |
| if (VG_(clo_trace_symtab)) |
| VG_(printf)( "%d merged\n", n_merged); |
| } |
| while (n_merged > 0); |
| |
| /* Detect and "fix" overlapping address ranges. */ |
| n_truncated = 0; |
| |
| for (i = 0; i < si->symtab_used-1; i++) { |
| |
| vg_assert(si->symtab[i].addr <= si->symtab[i+1].addr); |
| |
| /* Check for common (no overlap) case. */ |
| if (si->symtab[i].addr + si->symtab[i].size |
| <= si->symtab[i+1].addr) |
| continue; |
| |
| /* There's an overlap. Truncate one or the other. */ |
| if (VG_(clo_trace_symtab)) { |
| VG_(printf)("overlapping address ranges in symbol table\n\t"); |
| printSym(si,i); |
| VG_(printf)("\t"); |
| printSym(si,i+1); |
| VG_(printf)("\n"); |
| } |
| |
| /* Truncate one or the other. */ |
| s1 = si->symtab[i].addr; |
| s2 = si->symtab[i+1].addr; |
| e1 = s1 + si->symtab[i].size - 1; |
| e2 = s2 + si->symtab[i+1].size - 1; |
| if (s1 < s2) { |
| e1 = s2-1; |
| } else { |
| vg_assert(s1 == s2); |
| if (e1 > e2) { |
| s1 = e2+1; SWAP(Addr,s1,s2); SWAP(Addr,e1,e2); |
| } else |
| if (e1 < e2) { |
| s2 = e1+1; |
| } else { |
| /* e1 == e2. Identical addr ranges. We'll eventually wind |
| up back at cleanup_more, which will take care of it. */ |
| } |
| } |
| si->symtab[i].addr = s1; |
| si->symtab[i+1].addr = s2; |
| si->symtab[i].size = e1 - s1 + 1; |
| si->symtab[i+1].size = e2 - s2 + 1; |
| vg_assert(s1 <= s2); |
| vg_assert(si->symtab[i].size > 0); |
| vg_assert(si->symtab[i+1].size > 0); |
| /* It may be that the i+1 entry now needs to be moved further |
| along to maintain the address order requirement. */ |
| j = i+1; |
| while (j < si->symtab_used-1 |
| && si->symtab[j].addr > si->symtab[j+1].addr) { |
| SWAP(RiSym,si->symtab[j],si->symtab[j+1]); |
| j++; |
| } |
| n_truncated++; |
| } |
| |
| if (n_truncated > 0) goto cleanup_more; |
| |
| /* Ensure relevant postconditions hold. */ |
| for (i = 0; i < si->symtab_used-1; i++) { |
| /* No zero-sized symbols. */ |
| vg_assert(si->symtab[i].size > 0); |
| /* In order. */ |
| vg_assert(si->symtab[i].addr < si->symtab[i+1].addr); |
| /* No overlaps. */ |
| vg_assert(si->symtab[i].addr + si->symtab[i].size - 1 |
| < si->symtab[i+1].addr); |
| } |
| # undef SWAP |
| } |
| |
| |
| |
| /* Sort the location table by starting address. Mash the table around |
| so as to establish the property that addresses are in order and the |
| ranges do not overlap. This facilitates using binary search to map |
| addresses to locations when we come to query the table. */ |
| static |
| void canonicaliseLoctab ( SegInfo* si ) |
| { |
| /* Magic numbers due to Janet Incerpi and Robert Sedgewick. */ |
| Int incs[16] = { 1, 3, 7, 21, 48, 112, 336, 861, 1968, |
| 4592, 13776, 33936, 86961, 198768, |
| 463792, 1391376 }; |
| Int lo = 0; |
| Int hi = si->loctab_used-1; |
| Int i, j, h, bigN, hp; |
| RiLoc v; |
| |
| # define SWAP(ty,aa,bb) \ |
| do { ty tt = (aa); (aa) = (bb); (bb) = tt; } while (0); |
| |
| /* Sort by start address. */ |
| |
| bigN = hi - lo + 1; if (bigN < 2) return; |
| hp = 0; while (hp < 16 && incs[hp] < bigN) hp++; hp--; |
| vg_assert(0 <= hp && hp < 16); |
| |
| for (; hp >= 0; hp--) { |
| h = incs[hp]; |
| i = lo + h; |
| while (1) { |
| if (i > hi) break; |
| v = si->loctab[i]; |
| j = i; |
| while (si->loctab[j-h].addr > v.addr) { |
| si->loctab[j] = si->loctab[j-h]; |
| j = j - h; |
| if (j <= (lo + h - 1)) break; |
| } |
| si->loctab[j] = v; |
| i++; |
| } |
| } |
| |
| /* If two adjacent entries overlap, truncate the first. */ |
| for (i = 0; i < si->loctab_used-1; i++) { |
| vg_assert(si->loctab[i].size < 10000); |
| if (si->loctab[i].addr + si->loctab[i].size > si->loctab[i+1].addr) { |
| /* Do this in signed int32 because the actual .size fields |
| are unsigned 16s. */ |
| Int new_size = si->loctab[i+1].addr - si->loctab[i].addr; |
| if (new_size < 0) { |
| si->loctab[i].size = 0; |
| } else |
| if (new_size >= 65536) { |
| si->loctab[i].size = 65535; |
| } else { |
| si->loctab[i].size = (UShort)new_size; |
| } |
| } |
| } |
| |
| /* Zap any zero-sized entries resulting from the truncation |
| process. */ |
| j = 0; |
| for (i = 0; i < si->loctab_used; i++) { |
| if (si->loctab[i].size > 0) { |
| si->loctab[j] = si->loctab[i]; |
| j++; |
| } |
| } |
| si->loctab_used = j; |
| |
| /* Ensure relevant postconditions hold. */ |
| for (i = 0; i < si->loctab_used-1; i++) { |
| /* |
| VG_(printf)("%d (%d) %d 0x%x\n", |
| i, si->loctab[i+1].confident, |
| si->loctab[i+1].size, si->loctab[i+1].addr ); |
| */ |
| /* No zero-sized symbols. */ |
| vg_assert(si->loctab[i].size > 0); |
| /* In order. */ |
| vg_assert(si->loctab[i].addr < si->loctab[i+1].addr); |
| /* No overlaps. */ |
| vg_assert(si->loctab[i].addr + si->loctab[i].size - 1 |
| < si->loctab[i+1].addr); |
| } |
| # undef SWAP |
| } |
| |
| |
| /*------------------------------------------------------------*/ |
| /*--- Read info from a .so/exe file. ---*/ |
| /*------------------------------------------------------------*/ |
| |
| static __inline__ |
| void addLineInfo ( SegInfo* si, |
| Int fnmoff, |
| Addr this, |
| Addr next, |
| Int lineno, |
| Int entry ) |
| { |
| RiLoc loc; |
| Int size = next - this; |
| |
| /* Ignore zero-sized locs */ |
| if (this == next) return; |
| |
| /* Maximum sanity checking. Some versions of GNU as do a shabby job with |
| * stabs entries; if anything looks suspicious, revert to a size of 1. |
| * This should catch the instruction of interest (since if using asm-level |
| * debug info, one instruction will correspond to one line, unlike with |
| * C-level debug info where multiple instructions can map to the one line), |
| * but avoid catching any other instructions bogusly. */ |
| if (this > next) { |
| VG_(message)(Vg_DebugMsg, |
| "warning: stabs addresses out of order " |
| "at entry %d: 0x%x 0x%x", entry, this, next); |
| size = 1; |
| } |
| |
| if (size > MAX_LOC_SIZE) { |
| VG_(message)(Vg_DebugMsg, |
| "warning: stabs line address range too large " |
| "at entry %d: %d", entry, size); |
| size = 1; |
| } |
| |
| vg_assert(this < si->start + si->size && next-1 > si->start); |
| vg_assert(lineno >= 0 && lineno < MAX_LINENO); |
| |
| loc.addr = this; |
| loc.size = (UShort)size; |
| loc.lineno = lineno; |
| loc.fnmoff = fnmoff; |
| addLoc ( si, &loc ); |
| } |
| |
| |
| /* Read the symbols from the object/exe specified by the SegInfo into |
| the tables within the supplied SegInfo. */ |
| static |
| void vg_read_lib_symbols ( SegInfo* si ) |
| { |
| Elf32_Ehdr* ehdr; /* The ELF header */ |
| Elf32_Shdr* shdr; /* The section table */ |
| UChar* sh_strtab; /* The section table's string table */ |
| struct nlist* stab; /* The .stab table */ |
| UChar* stabstr; /* The .stab string table */ |
| Int stab_sz; /* Size in bytes of the .stab table */ |
| Int stabstr_sz; /* Size in bytes of the .stab string table */ |
| Int fd; |
| Int i; |
| Bool ok; |
| Addr oimage; |
| Int n_oimage; |
| struct stat stat_buf; |
| |
| /* for the .stabs reader */ |
| Int curr_filenmoff; |
| Addr curr_fnbaseaddr; |
| Char *curr_file_name, *curr_fn_name; |
| Int n_stab_entries; |
| Int prev_lineno, lineno; |
| Int lineno_overflows; |
| Bool same_file; |
| |
| oimage = (Addr)NULL; |
| if (VG_(clo_verbosity) > 1) |
| VG_(message)(Vg_UserMsg, "Reading syms from %s", si->filename ); |
| |
| /* mmap the object image aboard, so that we can read symbols and |
| line number info out of it. It will be munmapped immediately |
| thereafter; it is only aboard transiently. */ |
| |
| i = stat(si->filename, &stat_buf); |
| if (i != 0) { |
| vg_symerr("Can't stat .so/.exe (to determine its size)?!"); |
| return; |
| } |
| n_oimage = stat_buf.st_size; |
| |
| fd = VG_(open_read)(si->filename); |
| if (fd == -1) { |
| vg_symerr("Can't open .so/.exe to read symbols?!"); |
| return; |
| } |
| |
| oimage = (Addr)VG_(mmap)( NULL, n_oimage, PROT_READ, MAP_PRIVATE, fd, 0 ); |
| if (oimage == ((Addr)(-1))) { |
| VG_(message)(Vg_UserMsg, |
| "mmap failed on %s", si->filename ); |
| VG_(close)(fd); |
| return; |
| } |
| |
| VG_(close)(fd); |
| |
| /* Ok, the object image is safely in oimage[0 .. n_oimage-1]. |
| Now verify that it is a valid ELF .so or executable image. |
| */ |
| ok = (n_oimage >= sizeof(Elf32_Ehdr)); |
| ehdr = (Elf32_Ehdr*)oimage; |
| |
| if (ok) { |
| ok &= (ehdr->e_ident[EI_MAG0] == 0x7F |
| && ehdr->e_ident[EI_MAG1] == 'E' |
| && ehdr->e_ident[EI_MAG2] == 'L' |
| && ehdr->e_ident[EI_MAG3] == 'F'); |
| ok &= (ehdr->e_ident[EI_CLASS] == ELFCLASS32 |
| && ehdr->e_ident[EI_DATA] == ELFDATA2LSB |
| && ehdr->e_ident[EI_VERSION] == EV_CURRENT); |
| ok &= (ehdr->e_type == ET_EXEC || ehdr->e_type == ET_DYN); |
| ok &= (ehdr->e_machine == EM_386); |
| ok &= (ehdr->e_version == EV_CURRENT); |
| ok &= (ehdr->e_shstrndx != SHN_UNDEF); |
| ok &= (ehdr->e_shoff != 0 && ehdr->e_shnum != 0); |
| } |
| |
| if (!ok) { |
| vg_symerr("Invalid ELF header, or missing stringtab/sectiontab."); |
| VG_(munmap) ( (void*)oimage, n_oimage ); |
| return; |
| } |
| |
| if (VG_(clo_trace_symtab)) |
| VG_(printf)( |
| "shoff = %d, shnum = %d, size = %d, n_vg_oimage = %d\n", |
| ehdr->e_shoff, ehdr->e_shnum, sizeof(Elf32_Shdr), n_oimage ); |
| |
| if (ehdr->e_shoff + ehdr->e_shnum*sizeof(Elf32_Shdr) > n_oimage) { |
| vg_symerr("ELF section header is beyond image end?!"); |
| VG_(munmap) ( (void*)oimage, n_oimage ); |
| return; |
| } |
| |
| shdr = (Elf32_Shdr*)(oimage + ehdr->e_shoff); |
| sh_strtab = (UChar*)(oimage + shdr[ehdr->e_shstrndx].sh_offset); |
| |
| /* try and read the object's symbol table */ |
| { |
| UChar* o_strtab = NULL; |
| Elf32_Sym* o_symtab = NULL; |
| UInt o_strtab_sz = 0; |
| UInt o_symtab_sz = 0; |
| |
| UChar* o_got = NULL; |
| UChar* o_plt = NULL; |
| UInt o_got_sz = 0; |
| UInt o_plt_sz = 0; |
| |
| Bool snaffle_it; |
| Addr sym_addr; |
| |
| /* find the .stabstr and .stab sections */ |
| for (i = 0; i < ehdr->e_shnum; i++) { |
| if (0 == VG_(strcmp)(".symtab",sh_strtab + shdr[i].sh_name)) { |
| o_symtab = (Elf32_Sym*)(oimage + shdr[i].sh_offset); |
| o_symtab_sz = shdr[i].sh_size; |
| vg_assert((o_symtab_sz % sizeof(Elf32_Sym)) == 0); |
| /* check image overrun here */ |
| } |
| if (0 == VG_(strcmp)(".strtab",sh_strtab + shdr[i].sh_name)) { |
| o_strtab = (UChar*)(oimage + shdr[i].sh_offset); |
| o_strtab_sz = shdr[i].sh_size; |
| /* check image overrun here */ |
| } |
| |
| /* find out where the .got and .plt sections will be in the |
| executable image, not in the object image transiently loaded. |
| */ |
| if (0 == VG_(strcmp)(".got",sh_strtab + shdr[i].sh_name)) { |
| o_got = (UChar*)(si->offset |
| + shdr[i].sh_offset); |
| o_got_sz = shdr[i].sh_size; |
| /* check image overrun here */ |
| } |
| if (0 == VG_(strcmp)(".plt",sh_strtab + shdr[i].sh_name)) { |
| o_plt = (UChar*)(si->offset |
| + shdr[i].sh_offset); |
| o_plt_sz = shdr[i].sh_size; |
| /* check image overrun here */ |
| } |
| |
| } |
| |
| if (VG_(clo_trace_symtab)) { |
| if (o_plt) VG_(printf)( "PLT: %p .. %p\n", |
| o_plt, o_plt + o_plt_sz - 1 ); |
| if (o_got) VG_(printf)( "GOT: %p .. %p\n", |
| o_got, o_got + o_got_sz - 1 ); |
| } |
| |
| if (o_strtab == NULL || o_symtab == NULL) { |
| vg_symerr(" object doesn't have a symbol table"); |
| } else { |
| /* Perhaps should start at i = 1; ELF docs suggest that entry |
| 0 always denotes `unknown symbol'. */ |
| for (i = 1; i < o_symtab_sz/sizeof(Elf32_Sym); i++){ |
| # if 0 |
| VG_(printf)("raw symbol: "); |
| switch (ELF32_ST_BIND(o_symtab[i].st_info)) { |
| case STB_LOCAL: VG_(printf)("LOC "); break; |
| case STB_GLOBAL: VG_(printf)("GLO "); break; |
| case STB_WEAK: VG_(printf)("WEA "); break; |
| case STB_LOPROC: VG_(printf)("lop "); break; |
| case STB_HIPROC: VG_(printf)("hip "); break; |
| default: VG_(printf)("??? "); break; |
| } |
| switch (ELF32_ST_TYPE(o_symtab[i].st_info)) { |
| case STT_NOTYPE: VG_(printf)("NOT "); break; |
| case STT_OBJECT: VG_(printf)("OBJ "); break; |
| case STT_FUNC: VG_(printf)("FUN "); break; |
| case STT_SECTION: VG_(printf)("SEC "); break; |
| case STT_FILE: VG_(printf)("FIL "); break; |
| case STT_LOPROC: VG_(printf)("lop "); break; |
| case STT_HIPROC: VG_(printf)("hip "); break; |
| default: VG_(printf)("??? "); break; |
| } |
| VG_(printf)( |
| ": value %p, size %d, name %s\n", |
| si->offset+(UChar*)o_symtab[i].st_value, |
| o_symtab[i].st_size, |
| o_symtab[i].st_name |
| ? ((Char*)o_strtab+o_symtab[i].st_name) |
| : (Char*)"NONAME"); |
| # endif |
| |
| /* Figure out if we're interested in the symbol. |
| Firstly, is it of the right flavour? |
| */ |
| snaffle_it |
| = ( (ELF32_ST_BIND(o_symtab[i].st_info) == STB_GLOBAL || |
| ELF32_ST_BIND(o_symtab[i].st_info) == STB_LOCAL /* || |
| ELF32_ST_BIND(o_symtab[i].st_info) == STB_WEAK */) |
| && |
| (ELF32_ST_TYPE(o_symtab[i].st_info) == STT_FUNC /*|| |
| ELF32_ST_TYPE(o_symtab[i].st_info) == STT_OBJECT*/) |
| ); |
| |
| /* Secondly, if it's apparently in a GOT or PLT, it's really |
| a reference to a symbol defined elsewhere, so ignore it. |
| */ |
| sym_addr = si->offset |
| + (UInt)o_symtab[i].st_value; |
| if (o_got != NULL |
| && sym_addr >= (Addr)o_got |
| && sym_addr < (Addr)(o_got+o_got_sz)) { |
| snaffle_it = False; |
| if (VG_(clo_trace_symtab)) { |
| VG_(printf)( "in GOT: %s\n", |
| o_strtab+o_symtab[i].st_name); |
| } |
| } |
| if (o_plt != NULL |
| && sym_addr >= (Addr)o_plt |
| && sym_addr < (Addr)(o_plt+o_plt_sz)) { |
| snaffle_it = False; |
| if (VG_(clo_trace_symtab)) { |
| VG_(printf)( "in PLT: %s\n", |
| o_strtab+o_symtab[i].st_name); |
| } |
| } |
| |
| /* Don't bother if nameless, or zero-sized. */ |
| if (snaffle_it |
| && (o_symtab[i].st_name == (Elf32_Word)NULL |
| || /* VG_(strlen)(o_strtab+o_symtab[i].st_name) == 0 */ |
| /* equivalent but cheaper ... */ |
| * ((UChar*)(o_strtab+o_symtab[i].st_name)) == 0 |
| || o_symtab[i].st_size == 0)) { |
| snaffle_it = False; |
| if (VG_(clo_trace_symtab)) { |
| VG_(printf)( "size=0: %s\n", |
| o_strtab+o_symtab[i].st_name); |
| } |
| } |
| |
| # if 0 |
| /* Avoid _dl_ junk. (Why?) */ |
| /* 01-02-24: disabled until I find out if it really helps. */ |
| if (snaffle_it |
| && (VG_(strncmp)("_dl_", o_strtab+o_symtab[i].st_name, 4) == 0 |
| || VG_(strncmp)("_r_debug", |
| o_strtab+o_symtab[i].st_name, 8) == 0)) { |
| snaffle_it = False; |
| if (VG_(clo_trace_symtab)) { |
| VG_(printf)( "_dl_ junk: %s\n", |
| o_strtab+o_symtab[i].st_name); |
| } |
| } |
| # endif |
| |
| /* This seems to significantly reduce the number of junk |
| symbols, and particularly reduces the number of |
| overlapping address ranges. Don't ask me why ... */ |
| if (snaffle_it && (Int)o_symtab[i].st_value == 0) { |
| snaffle_it = False; |
| if (VG_(clo_trace_symtab)) { |
| VG_(printf)( "valu=0: %s\n", |
| o_strtab+o_symtab[i].st_name); |
| } |
| } |
| |
| /* If no part of the symbol falls within the mapped range, |
| ignore it. */ |
| if (sym_addr+o_symtab[i].st_size <= si->start |
| || sym_addr >= si->start+si->size) { |
| snaffle_it = False; |
| } |
| |
| if (snaffle_it) { |
| /* it's an interesting symbol; record ("snaffle") it. */ |
| RiSym sym; |
| Char* t0 = o_symtab[i].st_name |
| ? (Char*)(o_strtab+o_symtab[i].st_name) |
| : (Char*)"NONAME"; |
| Int nmoff = addStr ( si, t0 ); |
| vg_assert(nmoff >= 0 |
| /* && 0==VG_(strcmp)(t0,&vg_strtab[nmoff]) */ ); |
| vg_assert( (Int)o_symtab[i].st_value >= 0); |
| /* VG_(printf)("%p + %d: %s\n", si->addr, |
| (Int)o_symtab[i].st_value, t0 ); */ |
| sym.addr = sym_addr; |
| sym.size = o_symtab[i].st_size; |
| sym.nmoff = nmoff; |
| addSym ( si, &sym ); |
| } |
| } |
| } |
| } |
| |
| /* Reading of the "stabs" debug format information, if any. */ |
| stabstr = NULL; |
| stab = NULL; |
| stabstr_sz = 0; |
| stab_sz = 0; |
| /* find the .stabstr and .stab sections */ |
| for (i = 0; i < ehdr->e_shnum; i++) { |
| if (0 == VG_(strcmp)(".stab",sh_strtab + shdr[i].sh_name)) { |
| stab = (struct nlist *)(oimage + shdr[i].sh_offset); |
| stab_sz = shdr[i].sh_size; |
| } |
| if (0 == VG_(strcmp)(".stabstr",sh_strtab + shdr[i].sh_name)) { |
| stabstr = (UChar*)(oimage + shdr[i].sh_offset); |
| stabstr_sz = shdr[i].sh_size; |
| } |
| } |
| |
| if (stab == NULL || stabstr == NULL) { |
| vg_symerr(" object doesn't have any debug info"); |
| VG_(munmap) ( (void*)oimage, n_oimage ); |
| return; |
| } |
| |
| if ( stab_sz + (UChar*)stab > n_oimage + (UChar*)oimage |
| || stabstr_sz + (UChar*)stabstr |
| > n_oimage + (UChar*)oimage ) { |
| vg_symerr(" ELF debug data is beyond image end?!"); |
| VG_(munmap) ( (void*)oimage, n_oimage ); |
| return; |
| } |
| |
| /* Ok. It all looks plausible. Go on and read debug data. |
| stab kinds: 100 N_SO a source file name |
| 68 N_SLINE a source line number |
| 36 N_FUN start of a function |
| |
| In this loop, we maintain a current file name, updated as |
| N_SO/N_SOLs appear, and a current function base address, |
| updated as N_FUNs appear. Based on that, address ranges for |
| N_SLINEs are calculated, and stuffed into the line info table. |
| |
| Finding the instruction address range covered by an N_SLINE is |
| complicated; see the N_SLINE case below. |
| */ |
| curr_filenmoff = addStr(si,"???"); |
| curr_fnbaseaddr = (Addr)NULL; |
| curr_file_name = curr_fn_name = (Char*)NULL; |
| lineno = prev_lineno = 0; |
| lineno_overflows = 0; |
| same_file = True; |
| |
| n_stab_entries = stab_sz/(int)sizeof(struct nlist); |
| |
| for (i = 0; i < n_stab_entries; i++) { |
| # if 0 |
| VG_(printf) ( " %2d ", i ); |
| VG_(printf) ( "type=0x%x othr=%d desc=%d value=0x%x strx=%d %s", |
| stab[i].n_type, stab[i].n_other, stab[i].n_desc, |
| (int)stab[i].n_value, |
| (int)stab[i].n_un.n_strx, |
| stabstr + stab[i].n_un.n_strx ); |
| VG_(printf)("\n"); |
| # endif |
| |
| Char *no_fn_name = "???"; |
| |
| switch (stab[i].n_type) { |
| UInt next_addr; |
| |
| /* Two complicated things here: |
| * 1. the n_desc field in 'struct n_list' in a.out.h is only 16-bits, |
| * which gives a maximum of 65535 lines. We handle files bigger |
| * than this by detecting heuristically overflows -- if the line |
| * count goes from 65000-odd to 0-odd within the same file, we |
| * assume it's an overflow. Once we switch files, we zero the |
| * overflow count |
| * |
| * 2. To compute the instr address range covered by a single line, |
| * find the address of the next thing and compute the difference. |
| * The approach used depends on what kind of entry/entries |
| * follow... |
| */ |
| case N_SLINE: { |
| Int this_addr = (UInt)stab[i].n_value; |
| |
| /* Although stored as a short, neg values really are > 32768, hence |
| * the UShort cast. Then we use an Int to handle overflows. */ |
| prev_lineno = lineno; |
| lineno = (Int)((UShort)stab[i].n_desc); |
| |
| if (prev_lineno > lineno + OVERFLOW_DIFFERENCE && same_file) { |
| VG_(message)(Vg_DebugMsg, |
| "Line number overflow detected (%d --> %d) in %s", |
| prev_lineno, lineno, curr_file_name); |
| lineno_overflows++; |
| } |
| same_file = True; |
| |
| LOOP: |
| if (i+1 >= n_stab_entries) { |
| /* If it's the last entry, just guess the range is four; can't |
| * do any better */ |
| next_addr = this_addr + 4; |
| } else { |
| switch (stab[i+1].n_type) { |
| /* Easy, common case: use address of next entry */ |
| case N_SLINE: case N_SO: |
| next_addr = (UInt)stab[i+1].n_value; |
| break; |
| |
| /* Boring one: skip, look for something more useful. */ |
| case N_RSYM: case N_LSYM: case N_LBRAC: case N_RBRAC: |
| case N_STSYM: case N_LCSYM: case N_GSYM: |
| i++; |
| goto LOOP; |
| |
| /* Should be an end of fun entry, use its address */ |
| case N_FUN: |
| if ('\0' == * (stabstr + stab[i+1].n_un.n_strx) ) { |
| next_addr = (UInt)stab[i+1].n_value; |
| } else { |
| VG_(message)(Vg_DebugMsg, |
| "warning: function %s missing closing " |
| "N_FUN stab at entry %d", |
| curr_fn_name, i ); |
| next_addr = this_addr; /* assume zero-size loc */ |
| } |
| break; |
| |
| /* N_SOL should be followed by an N_SLINE which can be used */ |
| case N_SOL: |
| if (i+2 < n_stab_entries && N_SLINE == stab[i+2].n_type) { |
| next_addr = (UInt)stab[i+2].n_value; |
| break; |
| } else { |
| VG_(printf)("unhandled N_SOL stabs case: %d %d %d", |
| stab[i+1].n_type, i, n_stab_entries); |
| VG_(panic)("unhandled N_SOL stabs case"); |
| } |
| |
| default: |
| VG_(printf)("unhandled stabs case: %d %d", |
| stab[i+1].n_type,i); |
| VG_(panic)("unhandled (other) stabs case"); |
| } |
| } |
| |
| addLineInfo ( si, curr_filenmoff, curr_fnbaseaddr + this_addr, |
| curr_fnbaseaddr + next_addr, |
| lineno + lineno_overflows * LINENO_OVERFLOW, i); |
| break; |
| } |
| |
| case N_FUN: { |
| if ('\0' != (stabstr + stab[i].n_un.n_strx)[0] ) { |
| /* N_FUN with a name -- indicates the start of a fn. */ |
| curr_fnbaseaddr = si->offset + (Addr)stab[i].n_value; |
| curr_fn_name = stabstr + stab[i].n_un.n_strx; |
| } else { |
| curr_fn_name = no_fn_name; |
| } |
| break; |
| } |
| |
| case N_SOL: |
| if (lineno_overflows != 0) { |
| VG_(message)(Vg_UserMsg, |
| "Warning: file %s is very big (> 65535 lines) " |
| "Line numbers and annotation for this file might " |
| "be wrong. Sorry", |
| curr_file_name); |
| } |
| /* fall through! */ |
| case N_SO: |
| lineno_overflows = 0; |
| |
| /* seems to give lots of locations in header files */ |
| /* case 130: */ /* BINCL */ |
| { |
| UChar* nm = stabstr + stab[i].n_un.n_strx; |
| UInt len = VG_(strlen)(nm); |
| |
| if (len > 0 && nm[len-1] != '/') { |
| curr_filenmoff = addStr ( si, nm ); |
| curr_file_name = stabstr + stab[i].n_un.n_strx; |
| } |
| else |
| if (len == 0) |
| curr_filenmoff = addStr ( si, "?1\0" ); |
| |
| break; |
| } |
| |
| # if 0 |
| case 162: /* EINCL */ |
| curr_filenmoff = addStr ( si, "?2\0" ); |
| break; |
| # endif |
| |
| default: |
| break; |
| } |
| } /* for (i = 0; i < stab_sz/(int)sizeof(struct nlist); i++) */ |
| |
| /* Last, but not least, heave the oimage back overboard. */ |
| VG_(munmap) ( (void*)oimage, n_oimage ); |
| } |
| |
| |
| /*------------------------------------------------------------*/ |
| /*--- Main entry point for symbols table reading. ---*/ |
| /*------------------------------------------------------------*/ |
| |
| /* The root structure for the entire symbol table system. It is a |
| linked list of SegInfos. Note that this entire mechanism assumes |
| that what we read from /proc/self/maps doesn't contain overlapping |
| address ranges, and as a result the SegInfos in this list describe |
| disjoint address ranges. |
| */ |
| static SegInfo* segInfo = NULL; |
| |
| |
| static |
| void read_symtab_callback ( |
| Addr start, UInt size, |
| Char rr, Char ww, Char xx, |
| UInt foffset, UChar* filename ) |
| { |
| SegInfo* si; |
| |
| /* Stay sane ... */ |
| if (size == 0) |
| return; |
| |
| /* We're only interested in collecting symbols in executable |
| segments which are associated with a real file. Hence: */ |
| if (filename == NULL || xx != 'x') |
| return; |
| if (0 == VG_(strcmp)(filename, "/dev/zero")) |
| return; |
| |
| /* Perhaps we already have this one? If so, skip. */ |
| for (si = segInfo; si != NULL; si = si->next) { |
| /* |
| if (0==VG_(strcmp)(si->filename, filename)) |
| VG_(printf)("same fnames: %c%c%c (%p, %d) (%p, %d) %s\n", |
| rr,ww,xx,si->start,si->size,start,size,filename); |
| */ |
| /* For some reason the observed size of a mapping can change, so |
| we don't use that to determine uniqueness. */ |
| if (si->start == start |
| /* && si->size == size */ |
| && 0==VG_(strcmp)(si->filename, filename)) { |
| return; |
| } |
| } |
| |
| /* Get the record initialised right. */ |
| si = VG_(malloc)(VG_AR_SYMTAB, sizeof(SegInfo)); |
| si->next = segInfo; |
| segInfo = si; |
| |
| si->start = start; |
| si->size = size; |
| si->foffset = foffset; |
| si->filename = VG_(malloc)(VG_AR_SYMTAB, 1 + VG_(strlen)(filename)); |
| VG_(strcpy)(si->filename, filename); |
| |
| si->symtab = NULL; |
| si->symtab_size = si->symtab_used = 0; |
| si->loctab = NULL; |
| si->loctab_size = si->loctab_used = 0; |
| si->strtab = NULL; |
| si->strtab_size = si->strtab_used = 0; |
| |
| /* Kludge ... */ |
| si->offset |
| = si->start==VG_ASSUMED_EXE_BASE ? 0 : si->start; |
| |
| /* And actually fill it up. */ |
| vg_read_lib_symbols ( si ); |
| canonicaliseSymtab ( si ); |
| canonicaliseLoctab ( si ); |
| } |
| |
| |
| /* This one really is the Head Honcho. Update the symbol tables to |
| reflect the current state of /proc/self/maps. Rather than re-read |
| everything, just read the entries which are not already in segInfo. |
| So we can call here repeatedly, after every mmap of a non-anonymous |
| segment with execute permissions, for example, to pick up new |
| libraries as they are dlopen'd. Conversely, when the client does |
| munmap(), vg_symtab_notify_munmap() throws away any symbol tables |
| which happen to correspond to the munmap()d area. */ |
| void VG_(read_symbols) ( void ) |
| { |
| if (! VG_(clo_instrument) && ! VG_(clo_cachesim)) |
| return; |
| |
| VG_(read_procselfmaps) ( read_symtab_callback ); |
| |
| /* Do a sanity check on the symbol tables: ensure that the address |
| space pieces they cover do not overlap (otherwise we are severely |
| hosed). This is a quadratic algorithm, but there shouldn't be |
| many of them. |
| */ |
| { SegInfo *si, *si2; |
| for (si = segInfo; si != NULL; si = si->next) { |
| /* Check no overlap between *si and those in the rest of the |
| list. */ |
| for (si2 = si->next; si2 != NULL; si2 = si2->next) { |
| Addr lo = si->start; |
| Addr hi = si->start + si->size - 1; |
| Addr lo2 = si2->start; |
| Addr hi2 = si2->start + si2->size - 1; |
| Bool overlap; |
| vg_assert(lo < hi); |
| vg_assert(lo2 < hi2); |
| /* the main assertion */ |
| overlap = (lo <= lo2 && lo2 <= hi) |
| || (lo <= hi2 && hi2 <= hi); |
| //vg_assert(!overlap); |
| if (overlap) { |
| VG_(printf)("\n\nOVERLAPPING SEGMENTS\n" ); |
| ppSegInfo ( si ); |
| ppSegInfo ( si2 ); |
| VG_(printf)("\n\n"); |
| vg_assert(! overlap); |
| } |
| } |
| } |
| } |
| } |
| |
| |
| /* When an munmap() call happens, check to see whether it corresponds |
| to a segment for a .so, and if so discard the relevant SegInfo. |
| This might not be a very clever idea from the point of view of |
| accuracy of error messages, but we need to do it in order to |
| maintain the no-overlapping invariant. |
| */ |
| void VG_(symtab_notify_munmap) ( Addr start, UInt length ) |
| { |
| SegInfo *prev, *curr; |
| |
| if (! VG_(clo_instrument)) |
| return; |
| |
| prev = NULL; |
| curr = segInfo; |
| while (True) { |
| if (curr == NULL) break; |
| if (start == curr->start) break; |
| prev = curr; |
| curr = curr->next; |
| } |
| if (curr == NULL) return; |
| |
| VG_(message)(Vg_UserMsg, |
| "discard syms in %s due to munmap()", |
| curr->filename ? curr->filename : (UChar*)"???"); |
| |
| vg_assert(prev == NULL || prev->next == curr); |
| |
| if (prev == NULL) { |
| segInfo = curr->next; |
| } else { |
| prev->next = curr->next; |
| } |
| |
| freeSegInfo(curr); |
| } |
| |
| |
| /*------------------------------------------------------------*/ |
| /*--- Use of symbol table & location info to create ---*/ |
| /*--- plausible-looking stack dumps. ---*/ |
| /*------------------------------------------------------------*/ |
| |
| /* Find a symbol-table index containing the specified pointer, or -1 |
| if not found. Binary search. */ |
| |
| static Int search_one_symtab ( SegInfo* si, Addr ptr ) |
| { |
| Addr a_mid_lo, a_mid_hi; |
| Int mid, |
| lo = 0, |
| hi = si->symtab_used-1; |
| while (True) { |
| /* current unsearched space is from lo to hi, inclusive. */ |
| if (lo > hi) return -1; /* not found */ |
| mid = (lo + hi) / 2; |
| a_mid_lo = si->symtab[mid].addr; |
| a_mid_hi = ((Addr)si->symtab[mid].addr) + si->symtab[mid].size - 1; |
| |
| if (ptr < a_mid_lo) { hi = mid-1; continue; } |
| if (ptr > a_mid_hi) { lo = mid+1; continue; } |
| vg_assert(ptr >= a_mid_lo && ptr <= a_mid_hi); |
| return mid; |
| } |
| } |
| |
| |
| /* Search all symtabs that we know about to locate ptr. If found, set |
| *psi to the relevant SegInfo, and *symno to the symtab entry number |
| within that. If not found, *psi is set to NULL. */ |
| |
| static void search_all_symtabs ( Addr ptr, SegInfo** psi, Int* symno ) |
| { |
| Int sno; |
| SegInfo* si; |
| for (si = segInfo; si != NULL; si = si->next) { |
| if (si->start <= ptr && ptr < si->start+si->size) { |
| sno = search_one_symtab ( si, ptr ); |
| if (sno == -1) goto not_found; |
| *symno = sno; |
| *psi = si; |
| return; |
| } |
| } |
| not_found: |
| *psi = NULL; |
| } |
| |
| |
| /* Find a location-table index containing the specified pointer, or -1 |
| if not found. Binary search. */ |
| |
| static Int search_one_loctab ( SegInfo* si, Addr ptr ) |
| { |
| Addr a_mid_lo, a_mid_hi; |
| Int mid, |
| lo = 0, |
| hi = si->loctab_used-1; |
| while (True) { |
| /* current unsearched space is from lo to hi, inclusive. */ |
| if (lo > hi) return -1; /* not found */ |
| mid = (lo + hi) / 2; |
| a_mid_lo = si->loctab[mid].addr; |
| a_mid_hi = ((Addr)si->loctab[mid].addr) + si->loctab[mid].size - 1; |
| |
| if (ptr < a_mid_lo) { hi = mid-1; continue; } |
| if (ptr > a_mid_hi) { lo = mid+1; continue; } |
| vg_assert(ptr >= a_mid_lo && ptr <= a_mid_hi); |
| return mid; |
| } |
| } |
| |
| |
| /* Search all loctabs that we know about to locate ptr. If found, set |
| *psi to the relevant SegInfo, and *locno to the loctab entry number |
| within that. If not found, *psi is set to NULL. |
| */ |
| static void search_all_loctabs ( Addr ptr, SegInfo** psi, Int* locno ) |
| { |
| Int lno; |
| SegInfo* si; |
| for (si = segInfo; si != NULL; si = si->next) { |
| if (si->start <= ptr && ptr < si->start+si->size) { |
| lno = search_one_loctab ( si, ptr ); |
| if (lno == -1) goto not_found; |
| *locno = lno; |
| *psi = si; |
| return; |
| } |
| } |
| not_found: |
| *psi = NULL; |
| } |
| |
| |
| /* The whole point of this whole big deal: map a code address to a |
| plausible symbol name. Returns False if no idea; otherwise True. |
| Caller supplies buf and nbuf. If no_demangle is True, don't do |
| demangling, regardless of vg_clo_demangle -- probably because the |
| call has come from vg_what_fn_or_object_is_this. */ |
| Bool VG_(what_fn_is_this) ( Bool no_demangle, Addr a, |
| Char* buf, Int nbuf ) |
| { |
| SegInfo* si; |
| Int sno; |
| search_all_symtabs ( a, &si, &sno ); |
| if (si == NULL) |
| return False; |
| if (no_demangle) { |
| VG_(strncpy_safely) |
| ( buf, & si->strtab[si->symtab[sno].nmoff], nbuf ); |
| } else { |
| VG_(demangle) ( & si->strtab[si->symtab[sno].nmoff], buf, nbuf ); |
| } |
| return True; |
| } |
| |
| |
| /* Map a code address to the name of a shared object file. Returns |
| False if no idea; otherwise False. Caller supplies buf and |
| nbuf. */ |
| static |
| Bool vg_what_object_is_this ( Addr a, Char* buf, Int nbuf ) |
| { |
| SegInfo* si; |
| for (si = segInfo; si != NULL; si = si->next) { |
| if (si->start <= a && a < si->start+si->size) { |
| VG_(strncpy_safely)(buf, si->filename, nbuf); |
| return True; |
| } |
| } |
| return False; |
| } |
| |
| /* Return the name of an erring fn in a way which is useful |
| for comparing against the contents of a suppressions file. |
| Always writes something to buf. Also, doesn't demangle the |
| name, because we want to refer to mangled names in the |
| suppressions file. |
| */ |
| void VG_(what_obj_and_fun_is_this) ( Addr a, |
| Char* obj_buf, Int n_obj_buf, |
| Char* fun_buf, Int n_fun_buf ) |
| { |
| (void)vg_what_object_is_this ( a, obj_buf, n_obj_buf ); |
| (void)VG_(what_fn_is_this) ( True, a, fun_buf, n_fun_buf ); |
| } |
| |
| |
| /* Map a code address to a (filename, line number) pair. |
| Returns True if successful. |
| */ |
| Bool VG_(what_line_is_this)( Addr a, |
| UChar* filename, Int n_filename, |
| UInt* lineno ) |
| { |
| SegInfo* si; |
| Int locno; |
| search_all_loctabs ( a, &si, &locno ); |
| if (si == NULL) |
| return False; |
| VG_(strncpy_safely)(filename, & si->strtab[si->loctab[locno].fnmoff], |
| n_filename); |
| *lineno = si->loctab[locno].lineno; |
| |
| return True; |
| } |
| |
| |
| /* Print a mini stack dump, showing the current location. */ |
| void VG_(mini_stack_dump) ( ExeContext* ec ) |
| { |
| |
| #define APPEND(str) \ |
| { UChar* sss; \ |
| for (sss = str; n < M_VG_ERRTXT-1 && *sss != 0; n++,sss++) \ |
| buf[n] = *sss; \ |
| buf[n] = 0; \ |
| } |
| |
| Bool know_fnname; |
| Bool know_objname; |
| Bool know_srcloc; |
| UInt lineno; |
| UChar ibuf[20]; |
| UInt i, n, clueless; |
| |
| UChar buf[M_VG_ERRTXT]; |
| UChar buf_fn[M_VG_ERRTXT]; |
| UChar buf_obj[M_VG_ERRTXT]; |
| UChar buf_srcloc[M_VG_ERRTXT]; |
| |
| Int stop_at = VG_(clo_backtrace_size); |
| |
| n = 0; |
| |
| know_fnname = VG_(what_fn_is_this)(False,ec->eips[0], buf_fn, M_VG_ERRTXT); |
| know_objname = vg_what_object_is_this(ec->eips[0], buf_obj, M_VG_ERRTXT); |
| know_srcloc = VG_(what_line_is_this)(ec->eips[0], |
| buf_srcloc, M_VG_ERRTXT, |
| &lineno); |
| |
| APPEND(" at "); |
| VG_(sprintf)(ibuf,"0x%x: ", ec->eips[0]); |
| APPEND(ibuf); |
| if (know_fnname) { |
| APPEND(buf_fn); |
| if (!know_srcloc && know_objname) { |
| APPEND(" (in "); |
| APPEND(buf_obj); |
| APPEND(")"); |
| } |
| } else if (know_objname && !know_srcloc) { |
| APPEND("(within "); |
| APPEND(buf_obj); |
| APPEND(")"); |
| } else { |
| APPEND("???"); |
| } |
| if (know_srcloc) { |
| APPEND(" ("); |
| APPEND(buf_srcloc); |
| APPEND(":"); |
| VG_(sprintf)(ibuf,"%d",lineno); |
| APPEND(ibuf); |
| APPEND(")"); |
| } |
| VG_(message)(Vg_UserMsg, "%s", buf); |
| |
| clueless = 0; |
| for (i = 1; i < stop_at; i++) { |
| know_fnname = VG_(what_fn_is_this)(False,ec->eips[i], buf_fn, M_VG_ERRTXT); |
| know_objname = vg_what_object_is_this(ec->eips[i],buf_obj, M_VG_ERRTXT); |
| know_srcloc = VG_(what_line_is_this)(ec->eips[i], |
| buf_srcloc, M_VG_ERRTXT, |
| &lineno); |
| n = 0; |
| APPEND(" by "); |
| if (ec->eips[i] == 0) { |
| APPEND("<bogus frame pointer> "); |
| } else { |
| VG_(sprintf)(ibuf,"0x%x: ",ec->eips[i]); |
| APPEND(ibuf); |
| } |
| if (know_fnname) { |
| APPEND(buf_fn) |
| if (!know_srcloc && know_objname) { |
| APPEND(" (in "); |
| APPEND(buf_obj); |
| APPEND(")"); |
| } |
| } else { |
| if (know_objname && !know_srcloc) { |
| APPEND("(within "); |
| APPEND(buf_obj); |
| APPEND(")"); |
| } else { |
| APPEND("???"); |
| } |
| if (!know_srcloc) clueless++; |
| if (clueless == 2) |
| i = stop_at; /* force exit after this iteration */ |
| }; |
| if (know_srcloc) { |
| APPEND(" ("); |
| APPEND(buf_srcloc); |
| APPEND(":"); |
| VG_(sprintf)(ibuf,"%d",lineno); |
| APPEND(ibuf); |
| APPEND(")"); |
| } |
| VG_(message)(Vg_UserMsg, "%s", buf); |
| } |
| } |
| |
| #undef APPEND |
| |
| /*--------------------------------------------------------------------*/ |
| /*--- end vg_symtab2.c ---*/ |
| /*--------------------------------------------------------------------*/ |