diff options
Diffstat (limited to 'libbacktrace/xcoff.c')
| -rw-r--r-- | libbacktrace/xcoff.c | 1607 |
1 files changed, 1607 insertions, 0 deletions
diff --git a/libbacktrace/xcoff.c b/libbacktrace/xcoff.c new file mode 100644 index 0000000..2ded8f0 --- /dev/null +++ b/libbacktrace/xcoff.c @@ -0,0 +1,1607 @@ +/* xcoff.c -- Get debug data from an XCOFF file for backtraces. + Copyright (C) 2012-2021 Free Software Foundation, Inc. + Adapted from elf.c. + +Redistribution and use in source and binary forms, with or without +modification, are permitted provided that the following conditions are +met: + + (1) Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. + + (2) Redistributions in binary form must reproduce the above copyright + notice, this list of conditions and the following disclaimer in + the documentation and/or other materials provided with the + distribution. + + (3) The name of the author may not be used to + endorse or promote products derived from this software without + specific prior written permission. + +THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR +IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED +WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE +DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, +INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES +(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR +SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, +STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING +IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE +POSSIBILITY OF SUCH DAMAGE. */ + +#include "config.h" + +#include <errno.h> +#include <stdlib.h> +#include <string.h> +#include <sys/types.h> + +#ifdef HAVE_LOADQUERY +#include <sys/ldr.h> +#endif + +#include "backtrace.h" +#include "internal.h" + +/* The configure script must tell us whether we are 32-bit or 64-bit + XCOFF. We could make this code test and support either possibility, + but there is no point. This code only works for the currently + running executable, which means that we know the XCOFF mode at + configure time. */ + +#if BACKTRACE_XCOFF_SIZE != 32 && BACKTRACE_XCOFF_SIZE != 64 +#error "Unknown BACKTRACE_XCOFF_SIZE" +#endif + +/* XCOFF file header. */ + +#if BACKTRACE_XCOFF_SIZE == 32 + +typedef struct { + uint16_t f_magic; + uint16_t f_nscns; + uint32_t f_timdat; + uint32_t f_symptr; + uint32_t f_nsyms; + uint16_t f_opthdr; + uint16_t f_flags; +} b_xcoff_filhdr; + +#define XCOFF_MAGIC 0737 + +#else /* BACKTRACE_XCOFF_SIZE != 32 */ + +typedef struct { + uint16_t f_magic; + uint16_t f_nscns; + uint32_t f_timdat; + uint64_t f_symptr; + uint16_t f_opthdr; + uint16_t f_flags; + uint32_t f_nsyms; +} b_xcoff_filhdr; + +#define XCOFF_MAGIC 0767 + +#endif /* BACKTRACE_XCOFF_SIZE != 32 */ + +#define F_SHROBJ 0x2000 /* File is a shared object. */ + +/* XCOFF section header. */ + +#if BACKTRACE_XCOFF_SIZE == 32 + +typedef struct { + char s_name[8]; + uint32_t s_paddr; + uint32_t s_vaddr; + uint32_t s_size; + uint32_t s_scnptr; + uint32_t s_relptr; + uint32_t s_lnnoptr; + uint16_t s_nreloc; + uint16_t s_nlnno; + uint32_t s_flags; +} b_xcoff_scnhdr; + +#define _OVERFLOW_MARKER 65535 + +#else /* BACKTRACE_XCOFF_SIZE != 32 */ + +typedef struct { + char name[8]; + uint64_t s_paddr; + uint64_t s_vaddr; + uint64_t s_size; + uint64_t s_scnptr; + uint64_t s_relptr; + uint64_t s_lnnoptr; + uint32_t s_nreloc; + uint32_t s_nlnno; + uint32_t s_flags; +} b_xcoff_scnhdr; + +#endif /* BACKTRACE_XCOFF_SIZE != 32 */ + +#define STYP_DWARF 0x10 /* DWARF debugging section. */ +#define STYP_TEXT 0x20 /* Executable text (code) section. */ +#define STYP_OVRFLO 0x8000 /* Line-number field overflow section. */ + +#define SSUBTYP_DWINFO 0x10000 /* DWARF info section. */ +#define SSUBTYP_DWLINE 0x20000 /* DWARF line-number section. */ +#define SSUBTYP_DWARNGE 0x50000 /* DWARF aranges section. */ +#define SSUBTYP_DWABREV 0x60000 /* DWARF abbreviation section. */ +#define SSUBTYP_DWSTR 0x70000 /* DWARF strings section. */ +#define SSUBTYP_DWRNGES 0x80000 /* DWARF ranges section. */ + +/* XCOFF symbol. */ + +#define SYMNMLEN 8 + +#if BACKTRACE_XCOFF_SIZE == 32 + +typedef struct { + union { + char _name[SYMNMLEN]; + struct { + uint32_t _zeroes; + uint32_t _offset; + } _s; + } _u; +#define n_name _u._name +#define n_zeroes _u._s._zeroes +#define n_offset_ _u._s._offset + + uint32_t n_value; + int16_t n_scnum; + uint16_t n_type; + uint8_t n_sclass; + uint8_t n_numaux; +} __attribute__ ((packed)) b_xcoff_syment; + +#else /* BACKTRACE_XCOFF_SIZE != 32 */ + +typedef struct { + uint64_t n_value; + uint32_t n_offset_; + int16_t n_scnum; + uint16_t n_type; + uint8_t n_sclass; + uint8_t n_numaux; +} __attribute__ ((packed)) b_xcoff_syment; + +#endif /* BACKTRACE_XCOFF_SIZE != 32 */ + +#define SYMESZ 18 + +#define C_EXT 2 /* External symbol. */ +#define C_FCN 101 /* Beginning or end of function. */ +#define C_FILE 103 /* Source file name. */ +#define C_HIDEXT 107 /* Unnamed external symbol. */ +#define C_BINCL 108 /* Beginning of include file. */ +#define C_EINCL 109 /* End of include file. */ +#define C_WEAKEXT 111 /* Weak external symbol. */ + +#define ISFCN(x) ((x) & 0x0020) + +/* XCOFF AUX entry. */ + +#define AUXESZ 18 +#define FILNMLEN 14 + +typedef union { +#if BACKTRACE_XCOFF_SIZE == 32 + struct { + uint16_t pad; + uint16_t x_lnnohi; + uint16_t x_lnno; + } x_block; +#else + struct { + uint32_t x_lnno; + } x_block; +#endif + union { + char x_fname[FILNMLEN]; + struct { + uint32_t x_zeroes; + uint32_t x_offset; + char pad[FILNMLEN-8]; + uint8_t x_ftype; + } _x; + } x_file; +#if BACKTRACE_XCOFF_SIZE == 32 + struct { + uint32_t x_exptr; + uint32_t x_fsize; + uint32_t x_lnnoptr; + uint32_t x_endndx; + } x_fcn; +#else + struct { + uint64_t x_lnnoptr; + uint32_t x_fsize; + uint32_t x_endndx; + } x_fcn; +#endif + struct { + uint8_t pad[AUXESZ-1]; + uint8_t x_auxtype; + } x_auxtype; +} __attribute__ ((packed)) b_xcoff_auxent; + +/* XCOFF line number entry. */ + +#if BACKTRACE_XCOFF_SIZE == 32 + +typedef struct { + union { + uint32_t l_symndx; + uint32_t l_paddr; + } l_addr; + uint16_t l_lnno; +} b_xcoff_lineno; + +#define LINESZ 6 + +#else /* BACKTRACE_XCOFF_SIZE != 32 */ + +typedef struct { + union { + uint32_t l_symndx; + uint64_t l_paddr; + } l_addr; + uint32_t l_lnno; +} b_xcoff_lineno; + +#define LINESZ 12 + +#endif /* BACKTRACE_XCOFF_SIZE != 32 */ + +#if BACKTRACE_XCOFF_SIZE == 32 +#define XCOFF_AIX_TEXTBASE 0x10000000u +#else +#define XCOFF_AIX_TEXTBASE 0x100000000ul +#endif + +/* AIX big archive fixed-length header. */ + +#define AIAMAGBIG "<bigaf>\n" + +typedef struct { + char fl_magic[8]; /* Archive magic string. */ + char fl_memoff[20]; /* Offset to member table. */ + char fl_gstoff[20]; /* Offset to global symbol table. */ + char fl_gst64off[20]; /* Offset to global symbol table for 64-bit objects. */ + char fl_fstmoff[20]; /* Offset to first archive member. */ + char fl_freeoff[20]; /* Offset to first member on free list. */ +} b_ar_fl_hdr; + +/* AIX big archive file member header. */ + +typedef struct { + char ar_size[20]; /* File member size - decimal. */ + char ar_nxtmem[20]; /* Next member offset - decimal. */ + char ar_prvmem[20]; /* Previous member offset - decimal. */ + char ar_date[12]; /* File member date - decimal. */ + char ar_uid[12]; /* File member userid - decimal. */ + char ar_gid[12]; /* File member group id - decimal. */ + char ar_mode[12]; /* File member mode - octal. */ + char ar_namlen[4]; /* File member name length - decimal. */ + char ar_name[2]; /* Start of member name. */ +} b_ar_hdr; + + +/* Information we keep for an XCOFF symbol. */ + +struct xcoff_symbol +{ + /* The name of the symbol. */ + const char *name; + /* The address of the symbol. */ + uintptr_t address; + /* The size of the symbol. */ + size_t size; +}; + +/* Information to pass to xcoff_syminfo. */ + +struct xcoff_syminfo_data +{ + /* Symbols for the next module. */ + struct xcoff_syminfo_data *next; + /* The XCOFF symbols, sorted by address. */ + struct xcoff_symbol *symbols; + /* The number of symbols. */ + size_t count; +}; + +/* Information about an include file. */ + +struct xcoff_incl +{ + /* File name. */ + const char *filename; + /* Offset to first line number from the include file. */ + uintptr_t begin; + /* Offset to last line number from the include file. */ + uintptr_t end; +}; + +/* A growable vector of include files information. */ + +struct xcoff_incl_vector +{ + /* Memory. This is an array of struct xcoff_incl. */ + struct backtrace_vector vec; + /* Number of include files. */ + size_t count; +}; + +/* A growable vector of functions information. */ + +struct xcoff_func +{ + /* PC. */ + uintptr_t pc; + /* The size of the function. */ + size_t size; + /* Function name. */ + const char *name; + /* File name. */ + const char *filename; + /* Pointer to first lnno entry. */ + uintptr_t lnnoptr; + /* Base address of containing section. */ + uintptr_t sect_base; + /* Starting source line number. */ + int lnno; +}; + +/* A growable vector of function information. This is used while + reading the function symbols. */ + +struct xcoff_func_vector +{ + /* Memory. This is an array of struct xcoff_func. */ + struct backtrace_vector vec; + /* Number of valid mappings. */ + size_t count; +}; + +/* The information we need to map a PC to a file and line. */ + +struct xcoff_fileline_data +{ + /* The data for the next file we know about. */ + struct xcoff_fileline_data *next; + /* Functions information. */ + struct xcoff_func_vector func_vec; + /* Include files information. */ + struct xcoff_incl_vector incl_vec; + /* Line numbers information. */ + const unsigned char *linenos; + size_t linenos_size; + uint64_t lnnoptr0; + /* Loader address. */ + uintptr_t base_address; +}; + +/* Information we gather for the DWARF sections we care about. */ + +struct dwsect_info +{ + /* Section file offset. */ + off_t offset; + /* Section size. */ + size_t size; + /* Section contents, after read from file. */ + const unsigned char *data; +}; + +/* A dummy callback function used when we can't find any debug info. */ + +static int +xcoff_nodebug (struct backtrace_state *state ATTRIBUTE_UNUSED, + uintptr_t pc ATTRIBUTE_UNUSED, + backtrace_full_callback callback ATTRIBUTE_UNUSED, + backtrace_error_callback error_callback, void *data) +{ + error_callback (data, "no debug info in XCOFF executable", -1); + return 0; +} + +/* A dummy callback function used when we can't find a symbol + table. */ + +static void +xcoff_nosyms (struct backtrace_state *state ATTRIBUTE_UNUSED, + uintptr_t addr ATTRIBUTE_UNUSED, + backtrace_syminfo_callback callback ATTRIBUTE_UNUSED, + backtrace_error_callback error_callback, void *data) +{ + error_callback (data, "no symbol table in XCOFF executable", -1); +} + +/* Compare struct xcoff_symbol for qsort. */ + +static int +xcoff_symbol_compare (const void *v1, const void *v2) +{ + const struct xcoff_symbol *e1 = (const struct xcoff_symbol *) v1; + const struct xcoff_symbol *e2 = (const struct xcoff_symbol *) v2; + + if (e1->address < e2->address) + return -1; + else if (e1->address > e2->address) + return 1; + else + return 0; +} + +/* Compare an ADDR against an xcoff_symbol for bsearch. */ + +static int +xcoff_symbol_search (const void *vkey, const void *ventry) +{ + const uintptr_t *key = (const uintptr_t *) vkey; + const struct xcoff_symbol *entry = (const struct xcoff_symbol *) ventry; + uintptr_t addr; + + addr = *key; + if (addr < entry->address) + return -1; + else if ((entry->size == 0 && addr > entry->address) + || (entry->size > 0 && addr >= entry->address + entry->size)) + return 1; + else + return 0; +} + +/* Add XDATA to the list in STATE. */ + +static void +xcoff_add_syminfo_data (struct backtrace_state *state, + struct xcoff_syminfo_data *xdata) +{ + if (!state->threaded) + { + struct xcoff_syminfo_data **pp; + + for (pp = (struct xcoff_syminfo_data **) (void *) &state->syminfo_data; + *pp != NULL; + pp = &(*pp)->next) + ; + *pp = xdata; + } + else + { + while (1) + { + struct xcoff_syminfo_data **pp; + + pp = (struct xcoff_syminfo_data **) (void *) &state->syminfo_data; + + while (1) + { + struct xcoff_syminfo_data *p; + + p = backtrace_atomic_load_pointer (pp); + + if (p == NULL) + break; + + pp = &p->next; + } + + if (__sync_bool_compare_and_swap (pp, NULL, xdata)) + break; + } + } +} + +/* Return the symbol name and value for an ADDR. */ + +static void +xcoff_syminfo (struct backtrace_state *state ATTRIBUTE_UNUSED, uintptr_t addr, + backtrace_syminfo_callback callback, + backtrace_error_callback error_callback ATTRIBUTE_UNUSED, + void *data) +{ + struct xcoff_syminfo_data *edata; + struct xcoff_symbol *sym = NULL; + const char *name; + + if (!state->threaded) + { + for (edata = (struct xcoff_syminfo_data *) state->syminfo_data; + edata != NULL; + edata = edata->next) + { + sym = ((struct xcoff_symbol *) + bsearch (&addr, edata->symbols, edata->count, + sizeof (struct xcoff_symbol), xcoff_symbol_search)); + if (sym != NULL) + break; + } + } + else + { + struct xcoff_syminfo_data **pp; + + pp = (struct xcoff_syminfo_data **) (void *) &state->syminfo_data; + while (1) + { + edata = backtrace_atomic_load_pointer (pp); + if (edata == NULL) + break; + + sym = ((struct xcoff_symbol *) + bsearch (&addr, edata->symbols, edata->count, + sizeof (struct xcoff_symbol), xcoff_symbol_search)); + if (sym != NULL) + break; + + pp = &edata->next; + } + } + + if (sym == NULL) + callback (data, addr, NULL, 0, 0); + else + { + name = sym->name; + /* AIX prepends a '.' to function entry points, remove it. */ + if (name && *name == '.') + ++name; + callback (data, addr, name, sym->address, sym->size); + } +} + +/* Return the name of an XCOFF symbol. */ + +static const char * +xcoff_symname (const b_xcoff_syment *asym, + const unsigned char *strtab, size_t strtab_size) +{ +#if BACKTRACE_XCOFF_SIZE == 32 + if (asym->n_zeroes != 0) + { + /* Make a copy as we will release the symtab view. */ + char name[SYMNMLEN+1]; + strncpy (name, asym->n_name, SYMNMLEN); + name[SYMNMLEN] = '\0'; + return strdup (name); + } +#endif + if (asym->n_sclass & 0x80) + return NULL; /* .debug */ + if (asym->n_offset_ >= strtab_size) + return NULL; + return (const char *) strtab + asym->n_offset_; +} + +/* Initialize the symbol table info for xcoff_syminfo. */ + +static int +xcoff_initialize_syminfo (struct backtrace_state *state, + uintptr_t base_address, + const b_xcoff_syment *syms, size_t nsyms, + const unsigned char *strtab, size_t strtab_size, + backtrace_error_callback error_callback, void *data, + struct xcoff_syminfo_data *sdata) +{ + size_t xcoff_symbol_count; + size_t xcoff_symbol_size; + struct xcoff_symbol *xcoff_symbols; + size_t i; + unsigned int j; + + /* We only care about function symbols. Count them. */ + xcoff_symbol_count = 0; + for (i = 0; i < nsyms; ++i) + { + const b_xcoff_syment *asym = &syms[i]; + if ((asym->n_sclass == C_EXT || asym->n_sclass == C_HIDEXT + || asym->n_sclass == C_WEAKEXT) + && ISFCN (asym->n_type) && asym->n_numaux > 0 && asym->n_scnum > 0) + ++xcoff_symbol_count; + + i += asym->n_numaux; + } + + xcoff_symbol_size = xcoff_symbol_count * sizeof (struct xcoff_symbol); + xcoff_symbols = ((struct xcoff_symbol *) + backtrace_alloc (state, xcoff_symbol_size, error_callback, + data)); + if (xcoff_symbols == NULL) + return 0; + + j = 0; + for (i = 0; i < nsyms; ++i) + { + const b_xcoff_syment *asym = &syms[i]; + if ((asym->n_sclass == C_EXT || asym->n_sclass == C_HIDEXT + || asym->n_sclass == C_WEAKEXT) + && ISFCN (asym->n_type) && asym->n_numaux > 0 && asym->n_scnum > 0) + { + const b_xcoff_auxent *aux = (const b_xcoff_auxent *) (asym + 1); + xcoff_symbols[j].name = xcoff_symname (asym, strtab, strtab_size); + xcoff_symbols[j].address = base_address + asym->n_value; + /* x_fsize will be 0 if there is no debug information. */ + xcoff_symbols[j].size = aux->x_fcn.x_fsize; + ++j; + } + + i += asym->n_numaux; + } + + backtrace_qsort (xcoff_symbols, xcoff_symbol_count, + sizeof (struct xcoff_symbol), xcoff_symbol_compare); + + sdata->next = NULL; + sdata->symbols = xcoff_symbols; + sdata->count = xcoff_symbol_count; + + return 1; +} + +/* Compare struct xcoff_func for qsort. */ + +static int +xcoff_func_compare (const void *v1, const void *v2) +{ + const struct xcoff_func *fn1 = (const struct xcoff_func *) v1; + const struct xcoff_func *fn2 = (const struct xcoff_func *) v2; + + if (fn1->pc < fn2->pc) + return -1; + else if (fn1->pc > fn2->pc) + return 1; + else + return 0; +} + +/* Compare a PC against an xcoff_func for bsearch. */ + +static int +xcoff_func_search (const void *vkey, const void *ventry) +{ + const uintptr_t *key = (const uintptr_t *) vkey; + const struct xcoff_func *entry = (const struct xcoff_func *) ventry; + uintptr_t pc; + + pc = *key; + if (pc < entry->pc) + return -1; + else if ((entry->size == 0 && pc > entry->pc) + || (entry->size > 0 && pc >= entry->pc + entry->size)) + return 1; + else + return 0; +} + +/* Compare struct xcoff_incl for qsort. */ + +static int +xcoff_incl_compare (const void *v1, const void *v2) +{ + const struct xcoff_incl *in1 = (const struct xcoff_incl *) v1; + const struct xcoff_incl *in2 = (const struct xcoff_incl *) v2; + + if (in1->begin < in2->begin) + return -1; + else if (in1->begin > in2->begin) + return 1; + else + return 0; +} + +/* Find a lnnoptr in an include file. */ + +static int +xcoff_incl_search (const void *vkey, const void *ventry) +{ + const uintptr_t *key = (const uintptr_t *) vkey; + const struct xcoff_incl *entry = (const struct xcoff_incl *) ventry; + uintptr_t lnno; + + lnno = *key; + if (lnno < entry->begin) + return -1; + else if (lnno > entry->end) + return 1; + else + return 0; +} + +/* Look for a PC in the function vector for one module. On success, + call CALLBACK and return whatever it returns. On error, call + ERROR_CALLBACK and return 0. Sets *FOUND to 1 if the PC is found, + 0 if not. */ + +static int +xcoff_lookup_pc (struct backtrace_state *state ATTRIBUTE_UNUSED, + struct xcoff_fileline_data *fdata, uintptr_t pc, + backtrace_full_callback callback, + backtrace_error_callback error_callback ATTRIBUTE_UNUSED, + void *data, int *found) +{ + const struct xcoff_incl *incl, *bincl; + const struct xcoff_func *fn; + const b_xcoff_lineno *lineno; + const unsigned char *lineptr; + const char *function; + const char *filename; + uintptr_t lnnoptr, match; + uint32_t lnno = 0; + + *found = 1; + + if ((pc & 3) != 0) + ++pc; + + /* Find the function first. */ + fn = ((struct xcoff_func *) + bsearch (&pc, fdata->func_vec.vec.base, fdata->func_vec.count, + sizeof (struct xcoff_func), xcoff_func_search)); + if (fn == NULL) + { + *found = 0; + return 0; + } + + filename = fn->filename; + + /* Find the line number next. */ + + /* Skip first entry that points to symtab. */ + lnnoptr = fn->lnnoptr + LINESZ; + match = lnnoptr; + + lineptr = fdata->linenos + (lnnoptr - fdata->lnnoptr0); + while (lineptr + LINESZ <= fdata->linenos + fdata->linenos_size) + { + lineno = (const b_xcoff_lineno *) lineptr; + if (lineno->l_lnno == 0) + break; + if (pc <= fdata->base_address + lineno->l_addr.l_paddr) + break; + match = lnnoptr; + lnno = lineno->l_lnno; + + lnnoptr += LINESZ; + lineptr += LINESZ; + } + + /* If part of a function other than the beginning comes from an + include file, the line numbers are absolute, rather than + relative to the beginning of the function. */ + incl = ((struct xcoff_incl *) + bsearch (&match, fdata->incl_vec.vec.base, + fdata->incl_vec.count, sizeof (struct xcoff_incl), + xcoff_incl_search)); + if (incl != NULL) + { + bincl = ((struct xcoff_incl *) + bsearch (&fn->lnnoptr, fdata->incl_vec.vec.base, + fdata->incl_vec.count, sizeof (struct xcoff_incl), + xcoff_incl_search)); + if (bincl != NULL && strcmp (incl->filename, bincl->filename) == 0) + { + lnno += fn->lnno - 1; + } + filename = incl->filename; + } + else + { + lnno += fn->lnno - 1; + } + + function = fn->name; + /* AIX prepends a '.' to function entry points, remove it. */ + if (function != NULL && *function == '.') + ++function; + return callback (data, pc, filename, lnno, function); +} + +/* Return the file/line information for a PC using the XCOFF lineno + mapping we built earlier. */ + +static int +xcoff_fileline (struct backtrace_state *state, uintptr_t pc, + backtrace_full_callback callback, + backtrace_error_callback error_callback, void *data) + +{ + struct xcoff_fileline_data *fdata; + int found; + int ret; + + if (!state->threaded) + { + for (fdata = (struct xcoff_fileline_data *) state->fileline_data; + fdata != NULL; + fdata = fdata->next) + { + ret = xcoff_lookup_pc (state, fdata, pc, callback, error_callback, + data, &found); + if (ret != 0 || found) + return ret; + } + } + else + { + struct xcoff_fileline_data **pp; + + pp = (struct xcoff_fileline_data **) (void *) &state->fileline_data; + while (1) + { + fdata = backtrace_atomic_load_pointer (pp); + if (fdata == NULL) + break; + + ret = xcoff_lookup_pc (state, fdata, pc, callback, error_callback, + data, &found); + if (ret != 0 || found) + return ret; + + pp = &fdata->next; + } + } + + /* FIXME: See if any libraries have been dlopen'ed. */ + + return callback (data, pc, NULL, 0, NULL); +} + +/* Initialize the function vector info for xcoff_fileline. */ + +static int +xcoff_initialize_fileline (struct backtrace_state *state, + uintptr_t base_address, + const b_xcoff_scnhdr *sects, + const b_xcoff_syment *syms, size_t nsyms, + const unsigned char *strtab, size_t strtab_size, + const unsigned char *linenos, size_t linenos_size, + uint64_t lnnoptr0, + backtrace_error_callback error_callback, void *data) +{ + struct xcoff_fileline_data *fdata; + struct xcoff_func *fn; + const b_xcoff_syment *fsym; + const b_xcoff_auxent *aux; + const char *filename; + const char *name; + struct xcoff_incl *incl; + uintptr_t begin, end; + uintptr_t lnno, lnnoptr; + uint32_t fsize; + size_t i; + + fdata = ((struct xcoff_fileline_data *) + backtrace_alloc (state, sizeof (struct xcoff_fileline_data), + error_callback, data)); + if (fdata == NULL) + return 0; + memset (fdata, 0, sizeof *fdata); + fdata->base_address = base_address; + fdata->linenos = linenos; + fdata->linenos_size = linenos_size; + fdata->lnnoptr0 = lnnoptr0; + + begin = 0; + filename = NULL; + fsym = NULL; + lnnoptr = 0; + fsize = 0; + for (i = 0; i < nsyms; ++i) + { + const b_xcoff_syment *asym = &syms[i]; + + switch (asym->n_sclass) + { + case C_BINCL: + begin = asym->n_value; + break; + + case C_EINCL: + if (begin == 0) + break; + end = asym->n_value; + incl = ((struct xcoff_incl *) + backtrace_vector_grow (state, sizeof (struct xcoff_incl), + error_callback, data, + &fdata->incl_vec.vec)); + if (incl != NULL) + { + incl->filename = xcoff_symname (asym, strtab, strtab_size); + incl->begin = begin; + incl->end = end; + ++fdata->incl_vec.count; + } + begin = 0; + break; + + case C_FILE: + filename = xcoff_symname (asym, strtab, strtab_size); + if (filename == NULL) + break; + + /* If the file auxiliary entry is not used, the symbol name is + the name of the source file. If the file auxiliary entry is + used, then the symbol name should be .file, and the first + file auxiliary entry (by convention) contains the source + file name. */ + + if (asym->n_numaux > 0 && strcmp (filename, ".file") == 0) + { + aux = (const b_xcoff_auxent *) (asym + 1); + if (aux->x_file._x.x_zeroes != 0) + { + /* Make a copy as we will release the symtab view. */ + char name[FILNMLEN+1]; + strncpy (name, aux->x_file.x_fname, FILNMLEN); + name[FILNMLEN] = '\0'; + filename = strdup (name); + } + else if (aux->x_file._x.x_offset < strtab_size) + filename = (const char *) strtab + aux->x_file._x.x_offset; + else + filename = NULL; + } + break; + + case C_EXT: + case C_HIDEXT: + case C_WEAKEXT: + fsym = NULL; + lnnoptr = 0; + fsize = 0; + if (!ISFCN (asym->n_type) || asym->n_numaux == 0 + || asym->n_scnum <= 0) + break; + if (filename == NULL) + break; + aux = (const b_xcoff_auxent *) (asym + 1); + lnnoptr = aux->x_fcn.x_lnnoptr; + if (lnnoptr < lnnoptr0 + || lnnoptr + LINESZ > lnnoptr0 + linenos_size) + break; + /* x_fsize will be 0 if there is no debug information. */ + fsize = aux->x_fcn.x_fsize; + fsym = asym; + break; + + case C_FCN: + if (asym->n_numaux == 0) + break; + if (fsym == NULL) + break; + name = xcoff_symname (asym, strtab, strtab_size); + if (name == NULL || strcmp (name, ".bf") != 0) + { + fsym = NULL; + break; + } + aux = (const b_xcoff_auxent *) (asym + 1); +#if BACKTRACE_XCOFF_SIZE == 32 + lnno = (uint32_t) aux->x_block.x_lnnohi << 16 + | aux->x_block.x_lnno; +#else + lnno = aux->x_block.x_lnno; +#endif + fn = ((struct xcoff_func *) + backtrace_vector_grow (state, sizeof (struct xcoff_func), + error_callback, data, + &fdata->func_vec.vec)); + if (fn == NULL) + break; + fn->name = xcoff_symname (fsym, strtab, strtab_size); + fn->filename = filename; + fn->sect_base = sects[fsym->n_scnum - 1].s_paddr; + fn->pc = base_address + fsym->n_value; + fn->size = fsize; + fn->lnno = lnno; + fn->lnnoptr = lnnoptr; + ++fdata->func_vec.count; + break; + } + + i += asym->n_numaux; + } + + if (!backtrace_vector_release (state, &fdata->func_vec.vec, error_callback, + data)) + goto fail; + backtrace_qsort (fdata->func_vec.vec.base, fdata->func_vec.count, + sizeof (struct xcoff_func), xcoff_func_compare); + + if (!backtrace_vector_release (state, &fdata->incl_vec.vec, error_callback, + data)) + goto fail; + backtrace_qsort (fdata->incl_vec.vec.base, fdata->incl_vec.count, + sizeof (struct xcoff_incl), xcoff_incl_compare); + + if (!state->threaded) + { + struct xcoff_fileline_data **pp; + + for (pp = (struct xcoff_fileline_data **) (void *) &state->fileline_data; + *pp != NULL; + pp = &(*pp)->next) + ; + *pp = fdata; + } + else + { + while (1) + { + struct xcoff_fileline_data **pp; + + pp = (struct xcoff_fileline_data **) (void *) &state->fileline_data; + + while (1) + { + struct xcoff_fileline_data *p; + + p = backtrace_atomic_load_pointer (pp); + + if (p == NULL) + break; + + pp = &p->next; + } + + if (__sync_bool_compare_and_swap (pp, NULL, fdata)) + break; + } + } + + return 1; + +fail: + return 0; +} + +/* Add the backtrace data for one XCOFF file. Returns 1 on success, + 0 on failure (in both cases descriptor is closed). */ + +static int +xcoff_add (struct backtrace_state *state, int descriptor, off_t offset, + uintptr_t base_address, backtrace_error_callback error_callback, + void *data, fileline *fileline_fn, int *found_sym, int exe) +{ + struct backtrace_view fhdr_view; + struct backtrace_view sects_view; + struct backtrace_view linenos_view; + struct backtrace_view syms_view; + struct backtrace_view str_view; + struct backtrace_view dwarf_view; + b_xcoff_filhdr fhdr; + const b_xcoff_scnhdr *sects; + const b_xcoff_scnhdr *stext; + uint64_t lnnoptr; + uint32_t nlnno; + off_t str_off; + off_t min_offset; + off_t max_offset; + struct dwsect_info dwsect[DEBUG_MAX]; + size_t sects_size; + size_t syms_size; + int32_t str_size; + int sects_view_valid; + int linenos_view_valid; + int syms_view_valid; + int str_view_valid; + int dwarf_view_valid; + int magic_ok; + int i; + struct dwarf_sections dwarf_sections; + + *found_sym = 0; + + sects_view_valid = 0; + linenos_view_valid = 0; + syms_view_valid = 0; + str_view_valid = 0; + dwarf_view_valid = 0; + + str_size = 0; + + /* Map the XCOFF file header. */ + if (!backtrace_get_view (state, descriptor, offset, sizeof (b_xcoff_filhdr), + error_callback, data, &fhdr_view)) + goto fail; + + memcpy (&fhdr, fhdr_view.data, sizeof fhdr); + magic_ok = (fhdr.f_magic == XCOFF_MAGIC); + + backtrace_release_view (state, &fhdr_view, error_callback, data); + + if (!magic_ok) + { + if (exe) + error_callback (data, "executable file is not XCOFF", 0); + goto fail; + } + + /* Verify object is of expected type. */ + if ((exe && (fhdr.f_flags & F_SHROBJ)) + || (!exe && !(fhdr.f_flags & F_SHROBJ))) + goto fail; + + /* Read the section headers. */ + + sects_size = fhdr.f_nscns * sizeof (b_xcoff_scnhdr); + + if (!backtrace_get_view (state, descriptor, + offset + sizeof (fhdr) + fhdr.f_opthdr, + sects_size, error_callback, data, §s_view)) + goto fail; + sects_view_valid = 1; + sects = (const b_xcoff_scnhdr *) sects_view.data; + + /* FIXME: assumes only one .text section. */ + for (i = 0; i < fhdr.f_nscns; ++i) + if ((sects[i].s_flags & 0xffff) == STYP_TEXT) + break; + if (i == fhdr.f_nscns) + goto fail; + + stext = §s[i]; + + /* base_address represents the difference between the + virtual memory address of the shared object or a loaded + executable and the offset of that object in the file + from which it was loaded. + On AIX, virtual address is either fixed for executable + or given by ldinfo. This address will include the XCOFF + headers. */ + base_address = ((exe ? XCOFF_AIX_TEXTBASE : base_address) + + stext->s_scnptr + - stext->s_paddr); + + lnnoptr = stext->s_lnnoptr; + nlnno = stext->s_nlnno; + +#if BACKTRACE_XCOFF_SIZE == 32 + if (nlnno == _OVERFLOW_MARKER) + { + int sntext = i + 1; + /* Find the matching .ovrflo section. */ + for (i = 0; i < fhdr.f_nscns; ++i) + { + if (((sects[i].s_flags & 0xffff) == STYP_OVRFLO) + && sects[i].s_nlnno == sntext) + { + nlnno = sects[i].s_vaddr; + break; + } + } + } +#endif + + /* Read the symbol table and the string table. */ + + if (fhdr.f_symptr != 0) + { + struct xcoff_syminfo_data *sdata; + + /* Symbol table is followed by the string table. The string table + starts with its length (on 4 bytes). + Map the symbol table and the length of the string table. */ + syms_size = fhdr.f_nsyms * sizeof (b_xcoff_syment); + + if (!backtrace_get_view (state, descriptor, offset + fhdr.f_symptr, + syms_size + 4, error_callback, data, + &syms_view)) + goto fail; + syms_view_valid = 1; + + memcpy (&str_size, syms_view.data + syms_size, 4); + + str_off = fhdr.f_symptr + syms_size; + + if (str_size > 4) + { + /* Map string table (including the length word). */ + + if (!backtrace_get_view (state, descriptor, offset + str_off, + str_size, error_callback, data, &str_view)) + goto fail; + str_view_valid = 1; + } + + sdata = ((struct xcoff_syminfo_data *) + backtrace_alloc (state, sizeof *sdata, error_callback, data)); + if (sdata == NULL) + goto fail; + + if (!xcoff_initialize_syminfo (state, base_address, + syms_view.data, fhdr.f_nsyms, + str_view.data, str_size, + error_callback, data, sdata)) + { + backtrace_free (state, sdata, sizeof *sdata, error_callback, data); + goto fail; + } + + *found_sym = 1; + + xcoff_add_syminfo_data (state, sdata); + } + + /* Read all the DWARF sections in a single view, since they are + probably adjacent in the file. We never release this view. */ + + min_offset = 0; + max_offset = 0; + memset (dwsect, 0, sizeof dwsect); + for (i = 0; i < fhdr.f_nscns; ++i) + { + off_t end; + int idx; + + if ((sects[i].s_flags & 0xffff) != STYP_DWARF + || sects[i].s_size == 0) + continue; + /* Map DWARF section to array index. */ + switch (sects[i].s_flags & 0xffff0000) + { + case SSUBTYP_DWINFO: + idx = DEBUG_INFO; + break; + case SSUBTYP_DWLINE: + idx = DEBUG_LINE; + break; + case SSUBTYP_DWABREV: + idx = DEBUG_ABBREV; + break; + case SSUBTYP_DWRNGES: + idx = DEBUG_RANGES; + break; + case SSUBTYP_DWSTR: + idx = DEBUG_STR; + break; + default: + continue; + } + if (min_offset == 0 || (off_t) sects[i].s_scnptr < min_offset) + min_offset = sects[i].s_scnptr; + end = sects[i].s_scnptr + sects[i].s_size; + if (end > max_offset) + max_offset = end; + dwsect[idx].offset = sects[i].s_scnptr; + dwsect[idx].size = sects[i].s_size; + } + if (min_offset != 0 && max_offset != 0) + { + if (!backtrace_get_view (state, descriptor, offset + min_offset, + max_offset - min_offset, + error_callback, data, &dwarf_view)) + goto fail; + dwarf_view_valid = 1; + + for (i = 0; i < (int) DEBUG_MAX; ++i) + { + if (dwsect[i].offset == 0) + dwsect[i].data = NULL; + else + dwsect[i].data = ((const unsigned char *) dwarf_view.data + + (dwsect[i].offset - min_offset)); + } + + memset (&dwarf_sections, 0, sizeof dwarf_sections); + + dwarf_sections.data[DEBUG_INFO] = dwsect[DEBUG_INFO].data; + dwarf_sections.size[DEBUG_INFO] = dwsect[DEBUG_INFO].size; + dwarf_sections.data[DEBUG_LINE] = dwsect[DEBUG_LINE].data; + dwarf_sections.size[DEBUG_LINE] = dwsect[DEBUG_LINE].size; + dwarf_sections.data[DEBUG_ABBREV] = dwsect[DEBUG_ABBREV].data; + dwarf_sections.size[DEBUG_ABBREV] = dwsect[DEBUG_ABBREV].size; + dwarf_sections.data[DEBUG_RANGES] = dwsect[DEBUG_RANGES].data; + dwarf_sections.size[DEBUG_RANGES] = dwsect[DEBUG_RANGES].size; + dwarf_sections.data[DEBUG_STR] = dwsect[DEBUG_STR].data; + dwarf_sections.size[DEBUG_STR] = dwsect[DEBUG_STR].size; + + if (!backtrace_dwarf_add (state, base_address, &dwarf_sections, + 1, /* big endian */ + NULL, /* altlink */ + error_callback, data, fileline_fn, + NULL /* returned fileline_entry */)) + goto fail; + } + + /* Read the XCOFF line number entries if DWARF sections not found. */ + + if (!dwarf_view_valid && fhdr.f_symptr != 0 && lnnoptr != 0) + { + size_t linenos_size = (size_t) nlnno * LINESZ; + + /* We never release this view. */ + if (!backtrace_get_view (state, descriptor, offset + lnnoptr, + linenos_size, + error_callback, data, &linenos_view)) + goto fail; + linenos_view_valid = 1; + + if (xcoff_initialize_fileline (state, base_address, sects, + syms_view.data, fhdr.f_nsyms, + str_view.data, str_size, + linenos_view.data, linenos_size, + lnnoptr, error_callback, data)) + *fileline_fn = xcoff_fileline; + } + + backtrace_release_view (state, §s_view, error_callback, data); + sects_view_valid = 0; + if (syms_view_valid) + backtrace_release_view (state, &syms_view, error_callback, data); + syms_view_valid = 0; + + /* We've read all we need from the executable. */ + if (!backtrace_close (descriptor, error_callback, data)) + goto fail; + descriptor = -1; + + return 1; + + fail: + if (sects_view_valid) + backtrace_release_view (state, §s_view, error_callback, data); + if (str_view_valid) + backtrace_release_view (state, &str_view, error_callback, data); + if (syms_view_valid) + backtrace_release_view (state, &syms_view, error_callback, data); + if (linenos_view_valid) + backtrace_release_view (state, &linenos_view, error_callback, data); + if (dwarf_view_valid) + backtrace_release_view (state, &dwarf_view, error_callback, data); + if (descriptor != -1 && offset == 0) + backtrace_close (descriptor, error_callback, data); + return 0; +} + +#ifdef HAVE_LOADQUERY + +/* Read an integer value in human-readable format from an AIX + big archive fixed-length or member header. */ + +static int +xcoff_parse_decimal (const char *buf, size_t size, off_t *off) +{ + char str[32]; + char *end; + + if (size >= sizeof str) + return 0; + memcpy (str, buf, size); + str[size] = '\0'; + *off = strtol (str, &end, 10); + if (*end != '\0' && *end != ' ') + return 0; + + return 1; +} + +/* Add the backtrace data for a member of an AIX big archive. + Returns 1 on success, 0 on failure. */ + +static int +xcoff_armem_add (struct backtrace_state *state, int descriptor, + uintptr_t base_address, const char *member, + backtrace_error_callback error_callback, void *data, + fileline *fileline_fn, int *found_sym) +{ + struct backtrace_view view; + b_ar_fl_hdr fl_hdr; + const b_ar_hdr *ar_hdr; + off_t off; + off_t len; + int memlen; + + *found_sym = 0; + + /* Map archive fixed-length header. */ + + if (!backtrace_get_view (state, descriptor, 0, sizeof (b_ar_fl_hdr), + error_callback, data, &view)) + goto fail; + + memcpy (&fl_hdr, view.data, sizeof (b_ar_fl_hdr)); + + backtrace_release_view (state, &view, error_callback, data); + + if (memcmp (fl_hdr.fl_magic, AIAMAGBIG, 8) != 0) + goto fail; + + memlen = strlen (member); + + /* Read offset of first archive member. */ + if (!xcoff_parse_decimal (fl_hdr.fl_fstmoff, sizeof fl_hdr.fl_fstmoff, &off)) + goto fail; + while (off != 0) + { + /* Map archive member header and member name. */ + + if (!backtrace_get_view (state, descriptor, off, + sizeof (b_ar_hdr) + memlen, + error_callback, data, &view)) + break; + + ar_hdr = (const b_ar_hdr *) view.data; + + /* Read archive member name length. */ + if (!xcoff_parse_decimal (ar_hdr->ar_namlen, sizeof ar_hdr->ar_namlen, + &len)) + { + backtrace_release_view (state, &view, error_callback, data); + break; + } + if (len == memlen && !memcmp (ar_hdr->ar_name, member, memlen)) + { + off = (off + sizeof (b_ar_hdr) + memlen + 1) & ~1; + + /* The archive can contain several members with the same name + (e.g. 32-bit and 64-bit), so continue if not ok. */ + + if (xcoff_add (state, descriptor, off, base_address, error_callback, + data, fileline_fn, found_sym, 0)) + { + backtrace_release_view (state, &view, error_callback, data); + return 1; + } + } + + /* Read offset of next archive member. */ + if (!xcoff_parse_decimal (ar_hdr->ar_nxtmem, sizeof ar_hdr->ar_nxtmem, + &off)) + { + backtrace_release_view (state, &view, error_callback, data); + break; + } + backtrace_release_view (state, &view, error_callback, data); + } + + fail: + /* No matching member found. */ + backtrace_close (descriptor, error_callback, data); + return 0; +} + +/* Add the backtrace data for dynamically loaded libraries. */ + +static void +xcoff_add_shared_libs (struct backtrace_state *state, + backtrace_error_callback error_callback, + void *data, fileline *fileline_fn, int *found_sym) +{ + const struct ld_info *ldinfo; + void *buf; + unsigned int buflen; + const char *member; + int descriptor; + int does_not_exist; + int lib_found_sym; + int ret; + + /* Retrieve the list of loaded libraries. */ + + buf = NULL; + buflen = 512; + do + { + buf = realloc (buf, buflen); + if (buf == NULL) + { + ret = -1; + break; + } + ret = loadquery (L_GETINFO, buf, buflen); + if (ret == 0) + break; + buflen *= 2; + } + while (ret == -1 && errno == ENOMEM); + if (ret != 0) + { + free (buf); + return; + } + + ldinfo = (const struct ld_info *) buf; + while ((const char *) ldinfo < (const char *) buf + buflen) + { + if (*ldinfo->ldinfo_filename != '/') + goto next; + + descriptor = backtrace_open (ldinfo->ldinfo_filename, error_callback, + data, &does_not_exist); + if (descriptor < 0) + goto next; + + /* Check if it is an archive (member name not empty). */ + + member = ldinfo->ldinfo_filename + strlen (ldinfo->ldinfo_filename) + 1; + if (*member) + { + xcoff_armem_add (state, descriptor, + (uintptr_t) ldinfo->ldinfo_textorg, member, + error_callback, data, fileline_fn, &lib_found_sym); + } + else + { + xcoff_add (state, descriptor, 0, (uintptr_t) ldinfo->ldinfo_textorg, + error_callback, data, fileline_fn, &lib_found_sym, 0); + } + if (lib_found_sym) + *found_sym = 1; + + next: + if (ldinfo->ldinfo_next == 0) + break; + ldinfo = (const struct ld_info *) ((const char *) ldinfo + + ldinfo->ldinfo_next); + } + + free (buf); +} +#endif /* HAVE_LOADQUERY */ + +/* Initialize the backtrace data we need from an XCOFF executable. + Returns 1 on success, 0 on failure. */ + +int +backtrace_initialize (struct backtrace_state *state, + const char *filename ATTRIBUTE_UNUSED, int descriptor, + backtrace_error_callback error_callback, + void *data, fileline *fileline_fn) +{ + int ret; + int found_sym; + fileline xcoff_fileline_fn = xcoff_nodebug; + + ret = xcoff_add (state, descriptor, 0, 0, error_callback, data, + &xcoff_fileline_fn, &found_sym, 1); + if (!ret) + return 0; + +#ifdef HAVE_LOADQUERY + xcoff_add_shared_libs (state, error_callback, data, &xcoff_fileline_fn, + &found_sym); +#endif + + if (!state->threaded) + { + if (found_sym) + state->syminfo_fn = xcoff_syminfo; + else if (state->syminfo_fn == NULL) + state->syminfo_fn = xcoff_nosyms; + } + else + { + if (found_sym) + backtrace_atomic_store_pointer (&state->syminfo_fn, xcoff_syminfo); + else + (void) __sync_bool_compare_and_swap (&state->syminfo_fn, NULL, + xcoff_nosyms); + } + + if (!state->threaded) + { + if (state->fileline_fn == NULL || state->fileline_fn == xcoff_nodebug) + *fileline_fn = xcoff_fileline_fn; + } + else + { + fileline current_fn; + + current_fn = backtrace_atomic_load_pointer (&state->fileline_fn); + if (current_fn == NULL || current_fn == xcoff_nodebug) + *fileline_fn = xcoff_fileline_fn; + } + + return 1; +} |