diff --git a/debuggerd/Android.mk b/debuggerd/Android.mk index b22e1a81d..1dc842613 100644 --- a/debuggerd/Android.mk +++ b/debuggerd/Android.mk @@ -5,7 +5,7 @@ ifeq ($(TARGET_ARCH),arm) LOCAL_PATH:= $(call my-dir) include $(CLEAR_VARS) -LOCAL_SRC_FILES:= debuggerd.c getevent.c unwind-arm.c pr-support.c utility.c +LOCAL_SRC_FILES:= debuggerd.c getevent.c unwind-arm.c pr-support.c utility.c symbol_table.c LOCAL_CFLAGS := -Wall LOCAL_MODULE := debuggerd diff --git a/debuggerd/debuggerd.c b/debuggerd/debuggerd.c index 996e6c204..02bab2c63 100644 --- a/debuggerd/debuggerd.c +++ b/debuggerd/debuggerd.c @@ -55,7 +55,7 @@ static int logsocket = -1; /* Log information onto the tombstone */ void _LOG(int tfd, bool in_tombstone_only, const char *fmt, ...) { - char buf[128]; + char buf[512]; va_list ap; va_start(ap, fmt); @@ -98,10 +98,11 @@ mapinfo *parse_maps_line(char *line) mi->start = strtoul(line, 0, 16); mi->end = strtoul(line + 9, 0, 16); - /* To be filled in parse_exidx_info if the mapped section starts with + /* To be filled in parse_elf_info if the mapped section starts with * elf_header */ mi->exidx_start = mi->exidx_end = 0; + mi->symbols = 0; mi->next = 0; strcpy(mi->name, line + 49); @@ -335,7 +336,7 @@ void dump_crash_banner(int tfd, unsigned pid, unsigned tid, int sig) if(sig) dump_fault_addr(tfd, tid, sig); } -static void parse_exidx_info(mapinfo *milist, pid_t pid) +static void parse_elf_info(mapinfo *milist, pid_t pid) { mapinfo *mi; for (mi = milist; mi != NULL; mi = mi->next) { @@ -365,6 +366,9 @@ static void parse_exidx_info(mapinfo *milist, pid_t pid) break; } } + + /* Try to load symbols from this file */ + mi->symbols = symbol_table_create(mi->name); } } } @@ -402,7 +406,7 @@ void dump_crash_report(int tfd, unsigned pid, unsigned tid, bool at_fault) fclose(fp); } - parse_exidx_info(milist, tid); + parse_elf_info(milist, tid); /* If stack unwinder fails, use the default solution to dump the stack * content. @@ -422,6 +426,7 @@ void dump_crash_report(int tfd, unsigned pid, unsigned tid, bool at_fault) while(milist) { mapinfo *next = milist->next; + symbol_table_free(milist->symbols); free(milist); milist = next; } diff --git a/debuggerd/symbol_table.c b/debuggerd/symbol_table.c new file mode 100644 index 000000000..150c05832 --- /dev/null +++ b/debuggerd/symbol_table.c @@ -0,0 +1,178 @@ +#include +#include +#include +#include +#include + +#include "symbol_table.h" + +#include + +// Compare func for qsort +static int qcompar(const void *a, const void *b) +{ + return ((struct symbol*)a)->addr - ((struct symbol*)b)->addr; +} + +// Compare func for bsearch +static int bcompar(const void *addr, const void *element) +{ + struct symbol *symbol = (struct symbol*)element; + + if((unsigned int)addr < symbol->addr) { + return -1; + } + + if((unsigned int)addr - symbol->addr >= symbol->size) { + return 1; + } + + return 0; +} + +/* + * Create a symbol table from a given file + * + * Parameters: + * filename - Filename to process + * + * Returns: + * A newly-allocated SymbolTable structure, or NULL if error. + * Free symbol table with symbol_table_free() + */ +struct symbol_table *symbol_table_create(const char *filename) +{ + struct symbol_table *table = NULL; + + // Open the file, and map it into memory + struct stat sb; + int length; + char *base; + + int fd = open(filename, O_RDONLY); + + if(fd < 0) { + goto out; + } + + fstat(fd, &sb); + length = sb.st_size; + + base = mmap(NULL, length, PROT_READ, MAP_PRIVATE, fd, 0); + + if(!base) { + goto out_close; + } + + // Parse the file header + Elf32_Ehdr *hdr = (Elf32_Ehdr*)base; + Elf32_Shdr *shdr = (Elf32_Shdr*)(base + hdr->e_shoff); + + // Search for the dynamic symbols section + int dynsym_idx = -1; + int i; + + for(i = 0; i < hdr->e_shnum; i++) { + if(shdr[i].sh_type == SHT_DYNSYM ) { + dynsym_idx = i; + } + } + + if(dynsym_idx == -1) { + goto out_unmap; + } + + Elf32_Sym *dynsyms = (Elf32_Sym*)(base + shdr[dynsym_idx].sh_offset); + int numsyms = shdr[dynsym_idx].sh_size / shdr[dynsym_idx].sh_entsize; + + table = malloc(sizeof(struct symbol_table)); + if(!table) { + goto out_unmap; + } + table->num_symbols = 0; + + // Iterate through the dynamic symbol table, and count how many symbols + // are actually defined + for(i = 0; i < numsyms; i++) { + if(dynsyms[i].st_shndx != SHN_UNDEF) { + table->num_symbols++; + } + } + + int dynstr_idx = shdr[dynsym_idx].sh_link; + char *dynstr = base + shdr[dynstr_idx].sh_offset; + + // Now, create an entry in our symbol table structure for each symbol... + table->symbols = malloc(table->num_symbols * sizeof(struct symbol)); + if(!table->symbols) { + free(table); + table = NULL; + goto out_unmap; + } + + // ...and populate them + int j = 0; + for(i = 0; i < numsyms; i++) { + if(dynsyms[i].st_shndx != SHN_UNDEF) { + table->symbols[j].name = strdup(dynstr + dynsyms[i].st_name); + table->symbols[j].addr = dynsyms[i].st_value; + table->symbols[j].size = dynsyms[i].st_size; + j++; + } + } + + // Sort the symbol table entries, so they can be bsearched later + qsort(table->symbols, table->num_symbols, sizeof(struct symbol), qcompar); + +out_unmap: + munmap(base, length); + +out_close: + close(fd); + +out: + return table; +} + +/* + * Free a symbol table + * + * Parameters: + * table - Table to free + */ +void symbol_table_free(struct symbol_table *table) +{ + int i; + + if(!table) { + return; + } + + for(i=0; inum_symbols; i++) { + free(table->symbols[i].name); + } + + free(table->symbols); + free(table); +} + +/* + * Search for an address in the symbol table + * + * Parameters: + * table - Table to search in + * addr - Address to search for. + * + * Returns: + * A pointer to the Symbol structure corresponding to the + * symbol which contains this address, or NULL if no symbol + * contains it. + */ +const struct symbol *symbol_table_lookup(struct symbol_table *table, unsigned int addr) +{ + if(!table) { + return NULL; + } + + return bsearch((void*)addr, table->symbols, table->num_symbols, sizeof(struct symbol), bcompar); +} diff --git a/debuggerd/symbol_table.h b/debuggerd/symbol_table.h new file mode 100644 index 000000000..d9d252021 --- /dev/null +++ b/debuggerd/symbol_table.h @@ -0,0 +1,19 @@ +#ifndef SYMBOL_TABLE_H +#define SYMBOL_TABLE_H + +struct symbol { + unsigned int addr; + unsigned int size; + char *name; +}; + +struct symbol_table { + struct symbol *symbols; + int num_symbols; +}; + +struct symbol_table *symbol_table_create(const char *filename); +void symbol_table_free(struct symbol_table *table); +const struct symbol *symbol_table_lookup(struct symbol_table *table, unsigned int addr); + +#endif diff --git a/debuggerd/unwind-arm.c b/debuggerd/unwind-arm.c index 9642d2e4a..b081161a5 100644 --- a/debuggerd/unwind-arm.c +++ b/debuggerd/unwind-arm.c @@ -37,6 +37,8 @@ #include #include "utility.h" +#include "symbol_table.h" + typedef struct _ZSt9type_info type_info; /* This names C++ type_info type */ void __attribute__((weak)) __cxa_call_unexpected(_Unwind_Control_Block *ucbp); @@ -393,6 +395,7 @@ static _Unwind_Reason_Code log_function(_Unwind_Context *context, pid_t pid, phase2_vrs *vrs = (phase2_vrs*) context; const mapinfo *mi; bool only_in_tombstone = !at_fault; + const struct symbol* sym = 0; if (stack_level < STACK_CONTENT_DEPTH) { sp_list[stack_level] = vrs->core.r[R_SP]; @@ -451,9 +454,20 @@ static _Unwind_Reason_Code log_function(_Unwind_Context *context, pid_t pid, rel_pc = pc; mi = pc_to_mapinfo(map, pc, &rel_pc); - _LOG(tfd, only_in_tombstone, - " #%02d pc %08x %s\n", stack_level, rel_pc, - mi ? mi->name : ""); + /* See if we can determine what symbol this stack frame resides in */ + if (mi != 0 && mi->symbols != 0) { + sym = symbol_table_lookup(mi->symbols, rel_pc); + } + + if (sym) { + _LOG(tfd, only_in_tombstone, + " #%02d pc %08x %s (%s)\n", stack_level, rel_pc, + mi ? mi->name : "", sym->name); + } else { + _LOG(tfd, only_in_tombstone, + " #%02d pc %08x %s\n", stack_level, rel_pc, + mi ? mi->name : ""); + } return _URC_NO_REASON; } diff --git a/debuggerd/utility.h b/debuggerd/utility.h index 49f59518e..2ffdf5654 100644 --- a/debuggerd/utility.h +++ b/debuggerd/utility.h @@ -21,6 +21,8 @@ #include #include +#include "symbol_table.h" + #ifndef PT_ARM_EXIDX #define PT_ARM_EXIDX 0x70000001 /* .ARM.exidx segment */ #endif @@ -33,6 +35,7 @@ typedef struct mapinfo { unsigned end; unsigned exidx_start; unsigned exidx_end; + struct symbol_table *symbols; char name[]; } mapinfo;