The Design and Implementation of the FreeBSD Operating System, Second Edition
Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]

FreeBSD/Linux Kernel Cross Reference
sys/ddb/db_main.c

Version: -  FREEBSD  -  FREEBSD-13-STABLE  -  FREEBSD-13-0  -  FREEBSD-12-STABLE  -  FREEBSD-12-0  -  FREEBSD-11-STABLE  -  FREEBSD-11-0  -  FREEBSD-10-STABLE  -  FREEBSD-10-0  -  FREEBSD-9-STABLE  -  FREEBSD-9-0  -  FREEBSD-8-STABLE  -  FREEBSD-8-0  -  FREEBSD-7-STABLE  -  FREEBSD-7-0  -  FREEBSD-6-STABLE  -  FREEBSD-6-0  -  FREEBSD-5-STABLE  -  FREEBSD-5-0  -  FREEBSD-4-STABLE  -  FREEBSD-3-STABLE  -  FREEBSD22  -  l41  -  OPENBSD  -  linux-2.6  -  MK84  -  PLAN9  -  xnu-8792 
SearchContext: -  none  -  3  -  10 

    1 /*-
    2  * Mach Operating System
    3  * Copyright (c) 1991,1990 Carnegie Mellon University
    4  * All Rights Reserved.
    5  *
    6  * Permission to use, copy, modify and distribute this software and its
    7  * documentation is hereby granted, provided that both the copyright
    8  * notice and this permission notice appear in all copies of the
    9  * software, derivative works or modified versions, and any portions
   10  * thereof, and that both notices appear in supporting documentation.
   11  *
   12  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS
   13  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
   14  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
   15  *
   16  * Carnegie Mellon requests users of this software to return to
   17  *
   18  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
   19  *  School of Computer Science
   20  *  Carnegie Mellon University
   21  *  Pittsburgh PA 15213-3890
   22  *
   23  * any improvements or extensions that they make and grant Carnegie the
   24  * rights to redistribute these changes.
   25  */
   26 
   27 #include <sys/cdefs.h>
   28 __FBSDID("$FreeBSD$");
   29 
   30 #include <sys/param.h>
   31 #include <sys/systm.h>
   32 #include <sys/cons.h>
   33 #include <sys/linker.h>
   34 #include <sys/kdb.h>
   35 #include <sys/kernel.h>
   36 #include <sys/pcpu.h>
   37 #include <sys/proc.h>
   38 #include <sys/reboot.h>
   39 #include <sys/sysctl.h>
   40 
   41 #include <machine/kdb.h>
   42 #include <machine/pcb.h>
   43 #include <machine/setjmp.h>
   44 
   45 #include <ddb/ddb.h>
   46 #include <ddb/db_command.h>
   47 #include <ddb/db_sym.h>
   48 
   49 SYSCTL_NODE(_debug, OID_AUTO, ddb, CTLFLAG_RW, 0, "DDB settings");
   50 
   51 static dbbe_init_f db_init;
   52 static dbbe_trap_f db_trap;
   53 static dbbe_trace_f db_trace_self_wrapper;
   54 
   55 KDB_BACKEND(ddb, db_init, db_trace_self_wrapper, db_trap);
   56 
   57 vm_offset_t ksym_start, ksym_end;
   58 
   59 boolean_t
   60 X_db_line_at_pc(db_symtab_t *symtab, c_db_sym_t sym, char **file, int *line,
   61     db_expr_t off)
   62 {
   63         return (FALSE);
   64 }
   65 
   66 c_db_sym_t
   67 X_db_lookup(db_symtab_t *symtab, const char *symbol)
   68 {
   69         c_linker_sym_t lsym;
   70         Elf_Sym *sym;
   71 
   72         if (symtab->private == NULL) {
   73                 return ((c_db_sym_t)((!linker_ddb_lookup(symbol, &lsym))
   74                         ? lsym : NULL));
   75         } else {
   76                 sym = (Elf_Sym *)symtab->start;
   77                 while ((char *)sym < symtab->end) {
   78                         if (sym->st_name != 0 &&
   79                             !strcmp(symtab->private + sym->st_name, symbol))
   80                                 return ((c_db_sym_t)sym);
   81                         sym++;
   82                 }
   83         }
   84         return (NULL);
   85 }
   86 
   87 c_db_sym_t
   88 X_db_search_symbol(db_symtab_t *symtab, db_addr_t off, db_strategy_t strat,
   89     db_expr_t *diffp)
   90 {
   91         c_linker_sym_t lsym;
   92         Elf_Sym *sym, *match;
   93         unsigned long diff;
   94 
   95         if (symtab->private == NULL) {
   96                 if (!linker_ddb_search_symbol((caddr_t)off, &lsym, &diff)) {
   97                         *diffp = (db_expr_t)diff;
   98                         return ((c_db_sym_t)lsym);
   99                 }
  100                 return (NULL);
  101         }
  102 
  103         diff = ~0UL;
  104         match = NULL;
  105         for (sym = (Elf_Sym*)symtab->start; (char*)sym < symtab->end; sym++) {
  106                 if (sym->st_name == 0)
  107                         continue;
  108                 if (off < sym->st_value)
  109                         continue;
  110                 if (ELF_ST_TYPE(sym->st_info) != STT_OBJECT &&
  111                     ELF_ST_TYPE(sym->st_info) != STT_FUNC &&
  112                     ELF_ST_TYPE(sym->st_info) != STT_NOTYPE)
  113                         continue;
  114                 if ((off - sym->st_value) > diff)
  115                         continue;
  116                 if ((off - sym->st_value) < diff) {
  117                         diff = off - sym->st_value;
  118                         match = sym;
  119                 } else {
  120                         if (match == NULL)
  121                                 match = sym;
  122                         else if (ELF_ST_BIND(match->st_info) == STB_LOCAL &&
  123                             ELF_ST_BIND(sym->st_info) != STB_LOCAL)
  124                                 match = sym;
  125                 }
  126                 if (diff == 0) {
  127                         if (strat == DB_STGY_PROC &&
  128                             ELF_ST_TYPE(sym->st_info) == STT_FUNC &&
  129                             ELF_ST_BIND(sym->st_info) != STB_LOCAL)
  130                                 break;
  131                         if (strat == DB_STGY_ANY &&
  132                             ELF_ST_BIND(sym->st_info) != STB_LOCAL)
  133                                 break;
  134                 }
  135         }
  136 
  137         *diffp = (match == NULL) ? off : diff;
  138         return ((c_db_sym_t)match);
  139 }
  140 
  141 boolean_t
  142 X_db_sym_numargs(db_symtab_t *symtab, c_db_sym_t sym, int *nargp,
  143     char **argp)
  144 {
  145         return (FALSE);
  146 }
  147 
  148 void
  149 X_db_symbol_values(db_symtab_t *symtab, c_db_sym_t sym, const char **namep,
  150     db_expr_t *valp)
  151 {
  152         linker_symval_t lval;
  153 
  154         if (symtab->private == NULL) {
  155                 linker_ddb_symbol_values((c_linker_sym_t)sym, &lval);
  156                 if (namep != NULL)
  157                         *namep = (const char*)lval.name;
  158                 if (valp != NULL)
  159                         *valp = (db_expr_t)lval.value;
  160         } else {
  161                 if (namep != NULL)
  162                         *namep = (const char *)symtab->private +
  163                             ((const Elf_Sym *)sym)->st_name;
  164                 if (valp != NULL)
  165                         *valp = (db_expr_t)((const Elf_Sym *)sym)->st_value;
  166         }
  167 }
  168 
  169 static int
  170 db_init(void)
  171 {
  172         uintptr_t symtab, strtab;
  173         Elf_Size tabsz, strsz;
  174 
  175         if (ksym_end > ksym_start && ksym_start != 0) {
  176                 symtab = ksym_start;
  177                 tabsz = *((Elf_Size*)symtab);
  178                 symtab += sizeof(Elf_Size);
  179                 strtab = symtab + tabsz;
  180                 strsz = *((Elf_Size*)strtab);
  181                 strtab += sizeof(Elf_Size);
  182                 if (strtab + strsz <= ksym_end) {
  183                         db_add_symbol_table((char *)symtab,
  184                             (char *)(symtab + tabsz), "elf", (char *)strtab);
  185                 }
  186         }
  187         db_add_symbol_table(NULL, NULL, "kld", NULL);
  188         return (1);     /* We're the default debugger. */
  189 }
  190 
  191 static int
  192 db_trap(int type, int code)
  193 {
  194         jmp_buf jb;
  195         void *prev_jb;
  196         boolean_t bkpt, watchpt;
  197         const char *why;
  198 
  199         /*
  200          * Don't handle the trap if the console is unavailable (i.e. it
  201          * is in graphics mode).
  202          */
  203         if (cnunavailable())
  204                 return (0);
  205 
  206         bkpt = IS_BREAKPOINT_TRAP(type, code);
  207         watchpt = IS_WATCHPOINT_TRAP(type, code);
  208 
  209         if (db_stop_at_pc(&bkpt)) {
  210                 if (db_inst_count) {
  211                         db_printf("After %d instructions (%d loads, %d stores),\n",
  212                             db_inst_count, db_load_count, db_store_count);
  213                 }
  214                 prev_jb = kdb_jmpbuf(jb);
  215                 if (setjmp(jb) == 0) {
  216                         db_dot = PC_REGS();
  217                         db_print_thread();
  218                         if (bkpt)
  219                                 db_printf("Breakpoint at\t");
  220                         else if (watchpt)
  221                                 db_printf("Watchpoint at\t");
  222                         else
  223                                 db_printf("Stopped at\t");
  224                         db_print_loc_and_inst(db_dot);
  225                 }
  226                 why = kdb_why;
  227                 db_script_kdbenter(why != KDB_WHY_UNSET ? why : "unknown");
  228                 db_command_loop();
  229                 (void)kdb_jmpbuf(prev_jb);
  230         }
  231 
  232         db_restart_at_pc(watchpt);
  233 
  234         return (1);
  235 }
  236 
  237 static void
  238 db_trace_self_wrapper(void)
  239 {
  240         jmp_buf jb;
  241         void *prev_jb;
  242 
  243         prev_jb = kdb_jmpbuf(jb);
  244         if (setjmp(jb) == 0)
  245                 db_trace_self();
  246         (void)kdb_jmpbuf(prev_jb);
  247 }

Cache object: 5a6f653474778fbe4723721a4b7a490d


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]


This page is part of the FreeBSD/Linux Linux Kernel Cross-Reference, and was automatically generated using a modified version of the LXR engine.