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- /* Symbol, variable and name lookup.
- Copyright (C) 2019-2022 Free Software Foundation, Inc.
- This file is part of libctf.
- libctf 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 3, 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; see the file COPYING. If not see
- <http://www.gnu.org/licenses/>. */
- #include <ctf-impl.h>
- #include <elf.h>
- #include <string.h>
- #include <assert.h>
- /* Grow the pptrtab so that it is at least NEW_LEN long. */
- static int
- grow_pptrtab (ctf_dict_t *fp, size_t new_len)
- {
- uint32_t *new_pptrtab;
- if ((new_pptrtab = realloc (fp->ctf_pptrtab, sizeof (uint32_t)
- * new_len)) == NULL)
- return (ctf_set_errno (fp, ENOMEM));
- fp->ctf_pptrtab = new_pptrtab;
- memset (fp->ctf_pptrtab + fp->ctf_pptrtab_len, 0,
- sizeof (uint32_t) * (new_len - fp->ctf_pptrtab_len));
- fp->ctf_pptrtab_len = new_len;
- return 0;
- }
- /* Update entries in the pptrtab that relate to types newly added in the
- child. */
- static int
- refresh_pptrtab (ctf_dict_t *fp, ctf_dict_t *pfp)
- {
- uint32_t i;
- for (i = fp->ctf_pptrtab_typemax; i <= fp->ctf_typemax; i++)
- {
- ctf_id_t type = LCTF_INDEX_TO_TYPE (fp, i, 1);
- ctf_id_t reffed_type;
- if (ctf_type_kind (fp, type) != CTF_K_POINTER)
- continue;
- reffed_type = ctf_type_reference (fp, type);
- if (LCTF_TYPE_ISPARENT (fp, reffed_type))
- {
- uint32_t idx = LCTF_TYPE_TO_INDEX (fp, reffed_type);
- /* Guard against references to invalid types. No need to consider
- the CTF dict corrupt in this case: this pointer just can't be a
- pointer to any type we know about. */
- if (idx <= pfp->ctf_typemax)
- {
- if (idx >= fp->ctf_pptrtab_len
- && grow_pptrtab (fp, pfp->ctf_ptrtab_len) < 0)
- return -1; /* errno is set for us. */
- fp->ctf_pptrtab[idx] = i;
- }
- }
- }
- fp->ctf_pptrtab_typemax = fp->ctf_typemax;
- return 0;
- }
- /* Compare the given input string and length against a table of known C storage
- qualifier keywords. We just ignore these in ctf_lookup_by_name, below. To
- do this quickly, we use a pre-computed Perfect Hash Function similar to the
- technique originally described in the classic paper:
- R.J. Cichelli, "Minimal Perfect Hash Functions Made Simple",
- Communications of the ACM, Volume 23, Issue 1, January 1980, pp. 17-19.
- For an input string S of length N, we use hash H = S[N - 1] + N - 105, which
- for the current set of qualifiers yields a unique H in the range [0 .. 20].
- The hash can be modified when the keyword set changes as necessary. We also
- store the length of each keyword and check it prior to the final strcmp().
- TODO: just use gperf. */
- static int
- isqualifier (const char *s, size_t len)
- {
- static const struct qual
- {
- const char *q_name;
- size_t q_len;
- } qhash[] = {
- {"static", 6}, {"", 0}, {"", 0}, {"", 0},
- {"volatile", 8}, {"", 0}, {"", 0}, {"", 0}, {"", 0},
- {"", 0}, {"auto", 4}, {"extern", 6}, {"", 0}, {"", 0},
- {"", 0}, {"", 0}, {"const", 5}, {"register", 8},
- {"", 0}, {"restrict", 8}, {"_Restrict", 9}
- };
- int h = s[len - 1] + (int) len - 105;
- const struct qual *qp;
- if (h < 0 || (size_t) h >= sizeof (qhash) / sizeof (qhash[0]))
- return 0;
- qp = &qhash[h];
- return ((size_t) len == qp->q_len &&
- strncmp (qp->q_name, s, qp->q_len) == 0);
- }
- /* Attempt to convert the given C type name into the corresponding CTF type ID.
- It is not possible to do complete and proper conversion of type names
- without implementing a more full-fledged parser, which is necessary to
- handle things like types that are function pointers to functions that
- have arguments that are function pointers, and fun stuff like that.
- Instead, this function implements a very simple conversion algorithm that
- finds the things that we actually care about: structs, unions, enums,
- integers, floats, typedefs, and pointers to any of these named types. */
- static ctf_id_t
- ctf_lookup_by_name_internal (ctf_dict_t *fp, ctf_dict_t *child,
- const char *name)
- {
- static const char delimiters[] = " \t\n\r\v\f*";
- const ctf_lookup_t *lp;
- const char *p, *q, *end;
- ctf_id_t type = 0;
- ctf_id_t ntype, ptype;
- if (name == NULL)
- return (ctf_set_errno (fp, EINVAL));
- for (p = name, end = name + strlen (name); *p != '\0'; p = q)
- {
- while (isspace ((int) *p))
- p++; /* Skip leading whitespace. */
- if (p == end)
- break;
- if ((q = strpbrk (p + 1, delimiters)) == NULL)
- q = end; /* Compare until end. */
- if (*p == '*')
- {
- /* Find a pointer to type by looking in child->ctf_pptrtab (if child
- is set) and fp->ctf_ptrtab. If we can't find a pointer to the
- given type, see if we can compute a pointer to the type resulting
- from resolving the type down to its base type and use that instead.
- This helps with cases where the CTF data includes "struct foo *"
- but not "foo_t *" and the user tries to access "foo_t *" in the
- debugger.
- There is extra complexity here because uninitialized elements in
- the pptrtab and ptrtab are set to zero, but zero (as the type ID
- meaning the unimplemented type) is a valid return type from
- ctf_lookup_by_name. (Pointers to types are never of type 0, so
- this is unambiguous, just fiddly to deal with.) */
- uint32_t idx = LCTF_TYPE_TO_INDEX (fp, type);
- int in_child = 0;
- ntype = CTF_ERR;
- if (child && idx < child->ctf_pptrtab_len)
- {
- ntype = child->ctf_pptrtab[idx];
- if (ntype)
- in_child = 1;
- else
- ntype = CTF_ERR;
- }
- if (ntype == CTF_ERR)
- {
- ntype = fp->ctf_ptrtab[idx];
- if (ntype == 0)
- ntype = CTF_ERR;
- }
- /* Try resolving to its base type and check again. */
- if (ntype == CTF_ERR)
- {
- if (child)
- ntype = ctf_type_resolve_unsliced (child, type);
- else
- ntype = ctf_type_resolve_unsliced (fp, type);
- if (ntype == CTF_ERR)
- goto notype;
- idx = LCTF_TYPE_TO_INDEX (fp, ntype);
- ntype = CTF_ERR;
- if (child && idx < child->ctf_pptrtab_len)
- {
- ntype = child->ctf_pptrtab[idx];
- if (ntype)
- in_child = 1;
- else
- ntype = CTF_ERR;
- }
- if (ntype == CTF_ERR)
- {
- ntype = fp->ctf_ptrtab[idx];
- if (ntype == 0)
- ntype = CTF_ERR;
- }
- if (ntype == CTF_ERR)
- goto notype;
- }
- type = LCTF_INDEX_TO_TYPE (fp, ntype, (fp->ctf_flags & LCTF_CHILD)
- || in_child);
- /* We are looking up a type in the parent, but the pointed-to type is
- in the child. Switch to looking in the child: if we need to go
- back into the parent, we can recurse again. */
- if (in_child)
- {
- fp = child;
- child = NULL;
- }
- q = p + 1;
- continue;
- }
- if (isqualifier (p, (size_t) (q - p)))
- continue; /* Skip qualifier keyword. */
- for (lp = fp->ctf_lookups; lp->ctl_prefix != NULL; lp++)
- {
- /* TODO: This is not MT-safe. */
- if ((lp->ctl_prefix[0] == '\0' ||
- strncmp (p, lp->ctl_prefix, (size_t) (q - p)) == 0) &&
- (size_t) (q - p) >= lp->ctl_len)
- {
- for (p += lp->ctl_len; isspace ((int) *p); p++)
- continue; /* Skip prefix and next whitespace. */
- if ((q = strchr (p, '*')) == NULL)
- q = end; /* Compare until end. */
- while (isspace ((int) q[-1]))
- q--; /* Exclude trailing whitespace. */
- /* Expand and/or allocate storage for a slice of the name, then
- copy it in. */
- if (fp->ctf_tmp_typeslicelen >= (size_t) (q - p) + 1)
- {
- memcpy (fp->ctf_tmp_typeslice, p, (size_t) (q - p));
- fp->ctf_tmp_typeslice[(size_t) (q - p)] = '\0';
- }
- else
- {
- free (fp->ctf_tmp_typeslice);
- fp->ctf_tmp_typeslice = xstrndup (p, (size_t) (q - p));
- if (fp->ctf_tmp_typeslice == NULL)
- {
- ctf_set_errno (fp, ENOMEM);
- return CTF_ERR;
- }
- }
- if ((type = ctf_lookup_by_rawhash (fp, lp->ctl_hash,
- fp->ctf_tmp_typeslice)) == 0)
- goto notype;
- break;
- }
- }
- if (lp->ctl_prefix == NULL)
- goto notype;
- }
- if (*p != '\0' || type == 0)
- return (ctf_set_errno (fp, ECTF_SYNTAX));
- return type;
- notype:
- ctf_set_errno (fp, ECTF_NOTYPE);
- if (fp->ctf_parent != NULL)
- {
- /* Need to look up in the parent, from the child's perspective.
- Make sure the pptrtab is up to date. */
- if (fp->ctf_pptrtab_typemax < fp->ctf_typemax)
- {
- if (refresh_pptrtab (fp, fp->ctf_parent) < 0)
- return -1; /* errno is set for us. */
- }
- if ((ptype = ctf_lookup_by_name_internal (fp->ctf_parent, fp,
- name)) != CTF_ERR)
- return ptype;
- return (ctf_set_errno (fp, ctf_errno (fp->ctf_parent)));
- }
- return CTF_ERR;
- }
- ctf_id_t
- ctf_lookup_by_name (ctf_dict_t *fp, const char *name)
- {
- return ctf_lookup_by_name_internal (fp, NULL, name);
- }
- /* Return the pointer to the internal CTF type data corresponding to the
- given type ID. If the ID is invalid, the function returns NULL.
- This function is not exported outside of the library. */
- const ctf_type_t *
- ctf_lookup_by_id (ctf_dict_t **fpp, ctf_id_t type)
- {
- ctf_dict_t *fp = *fpp; /* Caller passes in starting CTF dict. */
- ctf_id_t idx;
- if ((fp = ctf_get_dict (fp, type)) == NULL)
- {
- (void) ctf_set_errno (*fpp, ECTF_NOPARENT);
- return NULL;
- }
- /* If this dict is writable, check for a dynamic type. */
- if (fp->ctf_flags & LCTF_RDWR)
- {
- ctf_dtdef_t *dtd;
- if ((dtd = ctf_dynamic_type (fp, type)) != NULL)
- {
- *fpp = fp;
- return &dtd->dtd_data;
- }
- (void) ctf_set_errno (*fpp, ECTF_BADID);
- return NULL;
- }
- /* Check for a type in the static portion. */
- idx = LCTF_TYPE_TO_INDEX (fp, type);
- if (idx > 0 && (unsigned long) idx <= fp->ctf_typemax)
- {
- *fpp = fp; /* Function returns ending CTF dict. */
- return (LCTF_INDEX_TO_TYPEPTR (fp, idx));
- }
- (void) ctf_set_errno (*fpp, ECTF_BADID);
- return NULL;
- }
- typedef struct ctf_lookup_idx_key
- {
- ctf_dict_t *clik_fp;
- const char *clik_name;
- uint32_t *clik_names;
- } ctf_lookup_idx_key_t;
- /* A bsearch function for variable names. */
- static int
- ctf_lookup_var (const void *key_, const void *lookup_)
- {
- const ctf_lookup_idx_key_t *key = key_;
- const ctf_varent_t *lookup = lookup_;
- return (strcmp (key->clik_name, ctf_strptr (key->clik_fp, lookup->ctv_name)));
- }
- /* Given a variable name, return the type of the variable with that name. */
- ctf_id_t
- ctf_lookup_variable (ctf_dict_t *fp, const char *name)
- {
- ctf_varent_t *ent;
- ctf_lookup_idx_key_t key = { fp, name, NULL };
- /* This array is sorted, so we can bsearch for it. */
- ent = bsearch (&key, fp->ctf_vars, fp->ctf_nvars, sizeof (ctf_varent_t),
- ctf_lookup_var);
- if (ent == NULL)
- {
- if (fp->ctf_parent != NULL)
- return ctf_lookup_variable (fp->ctf_parent, name);
- return (ctf_set_errno (fp, ECTF_NOTYPEDAT));
- }
- return ent->ctv_type;
- }
- typedef struct ctf_symidx_sort_arg_cb
- {
- ctf_dict_t *fp;
- uint32_t *names;
- } ctf_symidx_sort_arg_cb_t;
- static int
- sort_symidx_by_name (const void *one_, const void *two_, void *arg_)
- {
- const uint32_t *one = one_;
- const uint32_t *two = two_;
- ctf_symidx_sort_arg_cb_t *arg = arg_;
- return (strcmp (ctf_strptr (arg->fp, arg->names[*one]),
- ctf_strptr (arg->fp, arg->names[*two])));
- }
- /* Sort a symbol index section by name. Takes a 1:1 mapping of names to the
- corresponding symbol table. Returns a lexicographically sorted array of idx
- indexes (and thus, of indexes into the corresponding func info / data object
- section). */
- static uint32_t *
- ctf_symidx_sort (ctf_dict_t *fp, uint32_t *idx, size_t *nidx,
- size_t len)
- {
- uint32_t *sorted;
- size_t i;
- if ((sorted = malloc (len)) == NULL)
- {
- ctf_set_errno (fp, ENOMEM);
- return NULL;
- }
- *nidx = len / sizeof (uint32_t);
- for (i = 0; i < *nidx; i++)
- sorted[i] = i;
- if (!(fp->ctf_header->cth_flags & CTF_F_IDXSORTED))
- {
- ctf_symidx_sort_arg_cb_t arg = { fp, idx };
- ctf_dprintf ("Index section unsorted: sorting.");
- ctf_qsort_r (sorted, *nidx, sizeof (uint32_t), sort_symidx_by_name, &arg);
- fp->ctf_header->cth_flags |= CTF_F_IDXSORTED;
- }
- return sorted;
- }
- /* Given a symbol index, return the name of that symbol from the table provided
- by ctf_link_shuffle_syms, or failing that from the secondary string table, or
- the null string. */
- static const char *
- ctf_lookup_symbol_name (ctf_dict_t *fp, unsigned long symidx)
- {
- const ctf_sect_t *sp = &fp->ctf_symtab;
- ctf_link_sym_t sym;
- int err;
- if (fp->ctf_dynsymidx)
- {
- err = EINVAL;
- if (symidx > fp->ctf_dynsymmax)
- goto try_parent;
- ctf_link_sym_t *symp = fp->ctf_dynsymidx[symidx];
- if (!symp)
- goto try_parent;
- return symp->st_name;
- }
- err = ECTF_NOSYMTAB;
- if (sp->cts_data == NULL)
- goto try_parent;
- if (symidx >= fp->ctf_nsyms)
- goto try_parent;
- switch (sp->cts_entsize)
- {
- case sizeof (Elf64_Sym):
- {
- const Elf64_Sym *symp = (Elf64_Sym *) sp->cts_data + symidx;
- ctf_elf64_to_link_sym (fp, &sym, symp, symidx);
- }
- break;
- case sizeof (Elf32_Sym):
- {
- const Elf32_Sym *symp = (Elf32_Sym *) sp->cts_data + symidx;
- ctf_elf32_to_link_sym (fp, &sym, symp, symidx);
- }
- break;
- default:
- ctf_set_errno (fp, ECTF_SYMTAB);
- return _CTF_NULLSTR;
- }
- assert (!sym.st_nameidx_set);
- return sym.st_name;
- try_parent:
- if (fp->ctf_parent)
- {
- const char *ret;
- ret = ctf_lookup_symbol_name (fp->ctf_parent, symidx);
- if (ret == NULL)
- ctf_set_errno (fp, ctf_errno (fp->ctf_parent));
- return ret;
- }
- else
- {
- ctf_set_errno (fp, err);
- return _CTF_NULLSTR;
- }
- }
- /* Given a symbol name, return the index of that symbol, or -1 on error or if
- not found. */
- static unsigned long
- ctf_lookup_symbol_idx (ctf_dict_t *fp, const char *symname)
- {
- const ctf_sect_t *sp = &fp->ctf_symtab;
- ctf_link_sym_t sym;
- void *known_idx;
- int err;
- ctf_dict_t *cache = fp;
- if (fp->ctf_dynsyms)
- {
- err = EINVAL;
- ctf_link_sym_t *symp;
- if ((symp = ctf_dynhash_lookup (fp->ctf_dynsyms, symname)) == NULL)
- goto try_parent;
- return symp->st_symidx;
- }
- err = ECTF_NOSYMTAB;
- if (sp->cts_data == NULL)
- goto try_parent;
- /* First, try a hash lookup to see if we have already spotted this symbol
- during a past iteration: create the hash first if need be. The lifespan
- of the strings is equal to the lifespan of the cts_data, so we don't
- need to strdup them. If this dict was opened as part of an archive,
- and this archive has designed a crossdict_cache to cache results that
- are the same across all dicts in an archive, use it. */
- if (fp->ctf_archive && fp->ctf_archive->ctfi_crossdict_cache)
- cache = fp->ctf_archive->ctfi_crossdict_cache;
- if (!cache->ctf_symhash)
- if ((cache->ctf_symhash = ctf_dynhash_create (ctf_hash_string,
- ctf_hash_eq_string,
- NULL, NULL)) == NULL)
- goto oom;
- if (ctf_dynhash_lookup_kv (cache->ctf_symhash, symname, NULL, &known_idx))
- return (unsigned long) (uintptr_t) known_idx;
- /* Hash lookup unsuccessful: linear search, populating the hashtab for later
- lookups as we go. */
- for (; cache->ctf_symhash_latest < sp->cts_size / sp->cts_entsize;
- cache->ctf_symhash_latest++)
- {
- switch (sp->cts_entsize)
- {
- case sizeof (Elf64_Sym):
- {
- Elf64_Sym *symp = (Elf64_Sym *) sp->cts_data;
- ctf_elf64_to_link_sym (fp, &sym, &symp[cache->ctf_symhash_latest],
- cache->ctf_symhash_latest);
- if (!ctf_dynhash_lookup_kv (cache->ctf_symhash, sym.st_name,
- NULL, NULL))
- if (ctf_dynhash_cinsert (cache->ctf_symhash, sym.st_name,
- (const void *) (uintptr_t)
- cache->ctf_symhash_latest) < 0)
- goto oom;
- if (strcmp (sym.st_name, symname) == 0)
- return cache->ctf_symhash_latest++;
- }
- break;
- case sizeof (Elf32_Sym):
- {
- Elf32_Sym *symp = (Elf32_Sym *) sp->cts_data;
- ctf_elf32_to_link_sym (fp, &sym, &symp[cache->ctf_symhash_latest],
- cache->ctf_symhash_latest);
- if (!ctf_dynhash_lookup_kv (cache->ctf_symhash, sym.st_name,
- NULL, NULL))
- if (ctf_dynhash_cinsert (cache->ctf_symhash, sym.st_name,
- (const void *) (uintptr_t)
- cache->ctf_symhash_latest) < 0)
- goto oom;
- if (strcmp (sym.st_name, symname) == 0)
- return cache->ctf_symhash_latest++;
- }
- break;
- default:
- ctf_set_errno (fp, ECTF_SYMTAB);
- return (unsigned long) -1;
- }
- }
- /* Searched everything, still not found. */
- return (unsigned long) -1;
- try_parent:
- if (fp->ctf_parent)
- return ctf_lookup_symbol_idx (fp->ctf_parent, symname);
- else
- {
- ctf_set_errno (fp, err);
- return (unsigned long) -1;
- }
- oom:
- ctf_set_errno (fp, ENOMEM);
- ctf_err_warn (fp, 0, ENOMEM, _("cannot allocate memory for symbol "
- "lookup hashtab"));
- return (unsigned long) -1;
- }
- /* Iterate over all symbols with types: if FUNC, function symbols, otherwise,
- data symbols. The name argument is not optional. The return order is
- arbitrary, though is likely to be in symbol index or name order. You can
- change the value of 'functions' in the middle of iteration over non-dynamic
- dicts, but doing so on dynamic dicts will fail. (This is probably not very
- useful, but there is no reason to prohibit it.) */
- ctf_id_t
- ctf_symbol_next (ctf_dict_t *fp, ctf_next_t **it, const char **name,
- int functions)
- {
- ctf_id_t sym;
- ctf_next_t *i = *it;
- int err;
- if (!i)
- {
- if ((i = ctf_next_create ()) == NULL)
- return ctf_set_errno (fp, ENOMEM);
- i->cu.ctn_fp = fp;
- i->ctn_iter_fun = (void (*) (void)) ctf_symbol_next;
- i->ctn_n = 0;
- *it = i;
- }
- if ((void (*) (void)) ctf_symbol_next != i->ctn_iter_fun)
- return (ctf_set_errno (fp, ECTF_NEXT_WRONGFUN));
- if (fp != i->cu.ctn_fp)
- return (ctf_set_errno (fp, ECTF_NEXT_WRONGFP));
- /* We intentionally use raw access, not ctf_lookup_by_symbol, to avoid
- incurring additional sorting cost for unsorted symtypetabs coming from the
- compiler, to allow ctf_symbol_next to work in the absence of a symtab, and
- finally because it's easier to work out what the name of each symbol is if
- we do that. */
- if (fp->ctf_flags & LCTF_RDWR)
- {
- ctf_dynhash_t *dynh = functions ? fp->ctf_funchash : fp->ctf_objthash;
- void *dyn_name = NULL, *dyn_value = NULL;
- if (!dynh)
- {
- ctf_next_destroy (i);
- return (ctf_set_errno (fp, ECTF_NEXT_END));
- }
- err = ctf_dynhash_next (dynh, &i->ctn_next, &dyn_name, &dyn_value);
- /* This covers errors and also end-of-iteration. */
- if (err != 0)
- {
- ctf_next_destroy (i);
- *it = NULL;
- return ctf_set_errno (fp, err);
- }
- *name = dyn_name;
- sym = (ctf_id_t) (uintptr_t) dyn_value;
- }
- else if ((!functions && fp->ctf_objtidx_names) ||
- (functions && fp->ctf_funcidx_names))
- {
- ctf_header_t *hp = fp->ctf_header;
- uint32_t *idx = functions ? fp->ctf_funcidx_names : fp->ctf_objtidx_names;
- uint32_t *tab;
- size_t len;
- if (functions)
- {
- len = (hp->cth_varoff - hp->cth_funcidxoff) / sizeof (uint32_t);
- tab = (uint32_t *) (fp->ctf_buf + hp->cth_funcoff);
- }
- else
- {
- len = (hp->cth_funcidxoff - hp->cth_objtidxoff) / sizeof (uint32_t);
- tab = (uint32_t *) (fp->ctf_buf + hp->cth_objtoff);
- }
- do
- {
- if (i->ctn_n >= len)
- goto end;
- *name = ctf_strptr (fp, idx[i->ctn_n]);
- sym = tab[i->ctn_n++];
- }
- while (sym == -1u || sym == 0);
- }
- else
- {
- /* Skip over pads in ctf_xslate, padding for typeless symbols in the
- symtypetab itself, and symbols in the wrong table. */
- for (; i->ctn_n < fp->ctf_nsyms; i->ctn_n++)
- {
- ctf_header_t *hp = fp->ctf_header;
- if (fp->ctf_sxlate[i->ctn_n] == -1u)
- continue;
- sym = *(uint32_t *) ((uintptr_t) fp->ctf_buf + fp->ctf_sxlate[i->ctn_n]);
- if (sym == 0)
- continue;
- if (functions)
- {
- if (fp->ctf_sxlate[i->ctn_n] >= hp->cth_funcoff
- && fp->ctf_sxlate[i->ctn_n] < hp->cth_objtidxoff)
- break;
- }
- else
- {
- if (fp->ctf_sxlate[i->ctn_n] >= hp->cth_objtoff
- && fp->ctf_sxlate[i->ctn_n] < hp->cth_funcoff)
- break;
- }
- }
- if (i->ctn_n >= fp->ctf_nsyms)
- goto end;
- *name = ctf_lookup_symbol_name (fp, i->ctn_n++);
- }
- return sym;
- end:
- ctf_next_destroy (i);
- *it = NULL;
- return (ctf_set_errno (fp, ECTF_NEXT_END));
- }
- /* A bsearch function for function and object index names. */
- static int
- ctf_lookup_idx_name (const void *key_, const void *idx_)
- {
- const ctf_lookup_idx_key_t *key = key_;
- const uint32_t *idx = idx_;
- return (strcmp (key->clik_name, ctf_strptr (key->clik_fp, key->clik_names[*idx])));
- }
- /* Given a symbol name or (failing that) number, look up that symbol in the
- function or object index table (which must exist). Return 0 if not found
- there (or pad). */
- static ctf_id_t
- ctf_try_lookup_indexed (ctf_dict_t *fp, unsigned long symidx,
- const char *symname, int is_function)
- {
- struct ctf_header *hp = fp->ctf_header;
- uint32_t *symtypetab;
- uint32_t *names;
- uint32_t *sxlate;
- size_t nidx;
- if (symname == NULL)
- symname = ctf_lookup_symbol_name (fp, symidx);
- ctf_dprintf ("Looking up type of object with symtab idx %lx or name %s in "
- "indexed symtypetab\n", symidx, symname);
- if (symname[0] == '\0')
- return -1; /* errno is set for us. */
- if (is_function)
- {
- if (!fp->ctf_funcidx_sxlate)
- {
- if ((fp->ctf_funcidx_sxlate
- = ctf_symidx_sort (fp, (uint32_t *)
- (fp->ctf_buf + hp->cth_funcidxoff),
- &fp->ctf_nfuncidx,
- hp->cth_varoff - hp->cth_funcidxoff))
- == NULL)
- {
- ctf_err_warn (fp, 0, 0, _("cannot sort function symidx"));
- return -1; /* errno is set for us. */
- }
- }
- symtypetab = (uint32_t *) (fp->ctf_buf + hp->cth_funcoff);
- sxlate = fp->ctf_funcidx_sxlate;
- names = fp->ctf_funcidx_names;
- nidx = fp->ctf_nfuncidx;
- }
- else
- {
- if (!fp->ctf_objtidx_sxlate)
- {
- if ((fp->ctf_objtidx_sxlate
- = ctf_symidx_sort (fp, (uint32_t *)
- (fp->ctf_buf + hp->cth_objtidxoff),
- &fp->ctf_nobjtidx,
- hp->cth_funcidxoff - hp->cth_objtidxoff))
- == NULL)
- {
- ctf_err_warn (fp, 0, 0, _("cannot sort object symidx"));
- return -1; /* errno is set for us. */
- }
- }
- symtypetab = (uint32_t *) (fp->ctf_buf + hp->cth_objtoff);
- sxlate = fp->ctf_objtidx_sxlate;
- names = fp->ctf_objtidx_names;
- nidx = fp->ctf_nobjtidx;
- }
- ctf_lookup_idx_key_t key = { fp, symname, names };
- uint32_t *idx;
- idx = bsearch (&key, sxlate, nidx, sizeof (uint32_t), ctf_lookup_idx_name);
- if (!idx)
- {
- ctf_dprintf ("%s not found in idx\n", symname);
- return 0;
- }
- /* Should be impossible, but be paranoid. */
- if ((idx - sxlate) > (ptrdiff_t) nidx)
- return (ctf_set_errno (fp, ECTF_CORRUPT));
- ctf_dprintf ("Symbol %lx (%s) is of type %x\n", symidx, symname,
- symtypetab[*idx]);
- return symtypetab[*idx];
- }
- /* Given a symbol name or (if NULL) symbol index, return the type of the
- function or data object described by the corresponding entry in the symbol
- table. We can only return symbols in read-only dicts and in dicts for which
- ctf_link_shuffle_syms has been called to assign symbol indexes to symbol
- names. */
- static ctf_id_t
- ctf_lookup_by_sym_or_name (ctf_dict_t *fp, unsigned long symidx,
- const char *symname)
- {
- const ctf_sect_t *sp = &fp->ctf_symtab;
- ctf_id_t type = 0;
- int err = 0;
- /* Shuffled dynsymidx present? Use that. */
- if (fp->ctf_dynsymidx)
- {
- const ctf_link_sym_t *sym;
- if (symname)
- ctf_dprintf ("Looking up type of object with symname %s in "
- "writable dict symtypetab\n", symname);
- else
- ctf_dprintf ("Looking up type of object with symtab idx %lx in "
- "writable dict symtypetab\n", symidx);
- /* The dict must be dynamic. */
- if (!ctf_assert (fp, fp->ctf_flags & LCTF_RDWR))
- return CTF_ERR;
- /* No name? Need to look it up. */
- if (!symname)
- {
- err = EINVAL;
- if (symidx > fp->ctf_dynsymmax)
- goto try_parent;
- sym = fp->ctf_dynsymidx[symidx];
- err = ECTF_NOTYPEDAT;
- if (!sym || (sym->st_shndx != STT_OBJECT && sym->st_shndx != STT_FUNC))
- goto try_parent;
- if (!ctf_assert (fp, !sym->st_nameidx_set))
- return CTF_ERR;
- symname = sym->st_name;
- }
- if (fp->ctf_objthash == NULL
- || ((type = (ctf_id_t) (uintptr_t)
- ctf_dynhash_lookup (fp->ctf_objthash, symname)) == 0))
- {
- if (fp->ctf_funchash == NULL
- || ((type = (ctf_id_t) (uintptr_t)
- ctf_dynhash_lookup (fp->ctf_funchash, symname)) == 0))
- goto try_parent;
- }
- return type;
- }
- /* Lookup by name in a dynamic dict: just do it directly. */
- if (symname && fp->ctf_flags & LCTF_RDWR)
- {
- if (fp->ctf_objthash == NULL
- || ((type = (ctf_id_t) (uintptr_t)
- ctf_dynhash_lookup (fp->ctf_objthash, symname)) == 0))
- {
- if (fp->ctf_funchash == NULL
- || ((type = (ctf_id_t) (uintptr_t)
- ctf_dynhash_lookup (fp->ctf_funchash, symname)) == 0))
- goto try_parent;
- }
- return type;
- }
- err = ECTF_NOSYMTAB;
- if (sp->cts_data == NULL)
- goto try_parent;
- /* This covers both out-of-range lookups and a dynamic dict which hasn't been
- shuffled yet. */
- err = EINVAL;
- if (symname == NULL && symidx >= fp->ctf_nsyms)
- goto try_parent;
- if (fp->ctf_objtidx_names)
- {
- if ((type = ctf_try_lookup_indexed (fp, symidx, symname, 0)) == CTF_ERR)
- return CTF_ERR; /* errno is set for us. */
- }
- if (type == 0 && fp->ctf_funcidx_names)
- {
- if ((type = ctf_try_lookup_indexed (fp, symidx, symname, 1)) == CTF_ERR)
- return CTF_ERR; /* errno is set for us. */
- }
- if (type != 0)
- return type;
- err = ECTF_NOTYPEDAT;
- if (fp->ctf_objtidx_names && fp->ctf_funcidx_names)
- goto try_parent;
- /* Table must be nonindexed. */
- ctf_dprintf ("Looking up object type %lx in 1:1 dict symtypetab\n", symidx);
- if (symname != NULL)
- if ((symidx = ctf_lookup_symbol_idx (fp, symname)) == (unsigned long) -1)
- goto try_parent;
- if (fp->ctf_sxlate[symidx] == -1u)
- goto try_parent;
- type = *(uint32_t *) ((uintptr_t) fp->ctf_buf + fp->ctf_sxlate[symidx]);
- if (type == 0)
- goto try_parent;
- return type;
- try_parent:
- if (fp->ctf_parent)
- {
- ctf_id_t ret = ctf_lookup_by_sym_or_name (fp->ctf_parent, symidx,
- symname);
- if (ret == CTF_ERR)
- ctf_set_errno (fp, ctf_errno (fp->ctf_parent));
- return ret;
- }
- else
- return (ctf_set_errno (fp, err));
- }
- /* Given a symbol table index, return the type of the function or data object
- described by the corresponding entry in the symbol table. */
- ctf_id_t
- ctf_lookup_by_symbol (ctf_dict_t *fp, unsigned long symidx)
- {
- return ctf_lookup_by_sym_or_name (fp, symidx, NULL);
- }
- /* Given a symbol name, return the type of the function or data object described
- by the corresponding entry in the symbol table. */
- ctf_id_t
- ctf_lookup_by_symbol_name (ctf_dict_t *fp, const char *symname)
- {
- return ctf_lookup_by_sym_or_name (fp, 0, symname);
- }
- /* Given a symbol table index, return the info for the function described
- by the corresponding entry in the symbol table, which may be a function
- symbol or may be a data symbol that happens to be a function pointer. */
- int
- ctf_func_info (ctf_dict_t *fp, unsigned long symidx, ctf_funcinfo_t *fip)
- {
- ctf_id_t type;
- if ((type = ctf_lookup_by_symbol (fp, symidx)) == CTF_ERR)
- return -1; /* errno is set for us. */
- if (ctf_type_kind (fp, type) != CTF_K_FUNCTION)
- return (ctf_set_errno (fp, ECTF_NOTFUNC));
- return ctf_func_type_info (fp, type, fip);
- }
- /* Given a symbol table index, return the arguments for the function described
- by the corresponding entry in the symbol table. */
- int
- ctf_func_args (ctf_dict_t *fp, unsigned long symidx, uint32_t argc,
- ctf_id_t *argv)
- {
- ctf_id_t type;
- if ((type = ctf_lookup_by_symbol (fp, symidx)) == CTF_ERR)
- return -1; /* errno is set for us. */
- if (ctf_type_kind (fp, type) != CTF_K_FUNCTION)
- return (ctf_set_errno (fp, ECTF_NOTFUNC));
- return ctf_func_type_args (fp, type, argc, argv);
- }
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