From 8b526570440a2a1a8eff9c9991bf5ba103f829e4 Mon Sep 17 00:00:00 2001 From: Dima Kogan Date: Tue, 22 Apr 2014 16:22:08 -0700 Subject: reworked attr_numeric() to report failures This whole file is thus copyright me --- dwarf_prototypes.c | 112 +++++++++++++++++++++++++++++++++-------------------- 1 file changed, 71 insertions(+), 41 deletions(-) diff --git a/dwarf_prototypes.c b/dwarf_prototypes.c index 64d7820..936d94f 100644 --- a/dwarf_prototypes.c +++ b/dwarf_prototypes.c @@ -1,7 +1,4 @@ -/* Most of this is Copyright Dima Kogan - * - * Pieces of this were taken from dwarf_prototypes.c in the dwarves project. - * Those are Copyright (C) 2008 Arnaldo Carvalho de Melo . +/* Copyright Dima Kogan * * This program is free software; you can redistribute it and/or modify it under * the terms of version 2 of the GNU General Public License as published by the @@ -144,53 +141,62 @@ static bool dump_ltrace_tree(const struct arg_type_info* info) #endif - -static uint64_t attr_numeric(Dwarf_Die *die, uint32_t name) +// pulls a numerical value out of a particular attribute in a die. Returns true +// if successful. The result is returned in *result. Note that this is cast to +// (uint64_t), regardless of the actual type of the input +static bool get_die_numeric(uint64_t* result, + Dwarf_Die *die, unsigned int attr_name) { - Dwarf_Attribute attr; - uint32_t form; + Dwarf_Attribute attr ; - if (dwarf_attr(die, name, &attr) == NULL) - return 0; + union { + Dwarf_Word udata; + Dwarf_Sword sdata; + Dwarf_Addr addr; + bool flag; + } u; + + if (dwarf_attr(die, attr_name, &attr) == NULL) + return false; + + unsigned int form = dwarf_whatform(&attr); + +#define PROCESS_NUMERIC(type) \ + if (dwarf_form ## type(&attr, &u.type) != 0) \ + return false; \ + *result = (uint64_t)u.type; \ + return true - form = dwarf_whatform(&attr); switch (form) { - case DW_FORM_addr: { - Dwarf_Addr addr; - if (dwarf_formaddr(&attr, &addr) == 0) - return addr; - } - break; + case DW_FORM_addr: + PROCESS_NUMERIC(addr); + case DW_FORM_data1: case DW_FORM_data2: case DW_FORM_data4: case DW_FORM_data8: + case DW_FORM_udata: + PROCESS_NUMERIC(udata); + case DW_FORM_sdata: - case DW_FORM_udata: { - Dwarf_Word value; - if (dwarf_formudata(&attr, &value) == 0) - return value; - } - break; + PROCESS_NUMERIC(sdata); + case DW_FORM_flag: - case DW_FORM_flag_present: { - bool value; - if (dwarf_formflag(&attr, &value) == 0) - return value; - } - break; + PROCESS_NUMERIC(flag); + default: - complain(die, "DW_AT_<0x%x>=0x%x", name, form); - break; + complain(die, "Unknown numeric form %d for attr_name: %d", form, attr_name); + return false; } - - return 0; +#undef PROCESS_NUMERIC } static enum arg_type get_base_type(Dwarf_Die* die) { - int encoding = attr_numeric(die, DW_AT_encoding); + int64_t encoding; + if( !get_die_numeric((uint64_t*)&encoding, die, DW_AT_encoding) ) + return ARGTYPE_VOID; if (encoding == DW_ATE_void ) return ARGTYPE_VOID; @@ -198,11 +204,17 @@ static enum arg_type get_base_type(Dwarf_Die* die) if (encoding == DW_ATE_signed_char || encoding == DW_ATE_unsigned_char ) return ARGTYPE_CHAR; + uint64_t byte_size; + if (!get_die_numeric(&byte_size, die, DW_AT_byte_size)) + return ARGTYPE_VOID; + if (encoding == DW_ATE_signed || encoding == DW_ATE_unsigned || encoding == DW_ATE_boolean) { + bool is_signed = (encoding == DW_ATE_signed); - switch (attr_numeric(die, DW_AT_byte_size)) { + + switch (byte_size) { case sizeof(char): return ARGTYPE_CHAR; @@ -222,7 +234,7 @@ static enum arg_type get_base_type(Dwarf_Die* die) } if (encoding == DW_ATE_float) { - switch (attr_numeric(die, DW_AT_byte_size)) { + switch (byte_size) { case sizeof(float): return ARGTYPE_FLOAT; @@ -238,7 +250,7 @@ static enum arg_type get_base_type(Dwarf_Die* die) #if 0 if (encoding == DW_ATE_complex_float) { - switch (attr_numeric(die, DW_AT_byte_size)) { + switch (byte_size) { case 2*sizeof(float): return ARGTYPE_FLOAT; @@ -325,7 +337,13 @@ static bool get_enum(struct arg_type_info* enum_info, Dwarf_Die* parent) } value_init_detached(value, NULL, type_get_simple( ARGTYPE_INT ), 0); - value_set_word(value, attr_numeric(&die, DW_AT_const_value)); + uint64_t enum_value; + if (!get_die_numeric(&enum_value, &die, DW_AT_const_value)) { + complain(&die, "Couldn't get enum value"); + return false; + } + + value_set_word(value, (long)enum_value); if (lens_enum_add( lens, dupkey, 0, value, 0 )) { complain(&die, "Couldn't add enum element"); @@ -370,21 +388,33 @@ static bool get_array(struct arg_type_info* array_info, Dwarf_Die* parent) } if (dwarf_hasattr(&subrange, DW_AT_lower_bound)) { - if (attr_numeric(&subrange, DW_AT_lower_bound) != 0) { + uint64_t lower_bound; + if (!get_die_numeric(&lower_bound, &subrange, DW_AT_lower_bound)) { + complain( parent, "Couldn't read lower bound"); + return false; + } + + if (lower_bound != 0) { complain( parent, "Array subrange has a nonzero lower bound. Don't know what to do"); return false; } } - int N; + uint64_t N; if (!dwarf_hasattr(&subrange, DW_AT_upper_bound)) { // no upper bound is defined. This is probably a variable-width array, // and I don't know how long it is. Let's say 0 to be safe N = 0; } else - N = attr_numeric(&subrange, DW_AT_upper_bound)+1; + { + if (!get_die_numeric(&N, &subrange, DW_AT_upper_bound)) { + complain( parent, "Couldn't read upper bound"); + return false; + } + N++; + } // I'm not checking the subrange type. It should be some sort of integer, // and I don't know what it would mean for it to be something else -- cgit v1.2.3