diff options
Diffstat (limited to 'libdwfl/dwfl_getmodules.c')
| -rw-r--r-- | libdwfl/dwfl_getmodules.c | 54 |
1 files changed, 47 insertions, 7 deletions
diff --git a/libdwfl/dwfl_getmodules.c b/libdwfl/dwfl_getmodules.c index 45e550a5..7c6ab971 100644 --- a/libdwfl/dwfl_getmodules.c +++ b/libdwfl/dwfl_getmodules.c @@ -1,5 +1,5 @@ /* Iterate through modules. - Copyright (C) 2005 Red Hat, Inc. + Copyright (C) 2005, 2008 Red Hat, Inc. This file is part of Red Hat elfutils. Red Hat elfutils is free software; you can redistribute it and/or modify @@ -59,15 +59,55 @@ dwfl_getmodules (Dwfl *dwfl, if (dwfl == NULL) return -1; - if ((size_t) offset > dwfl->nmodules) - return -1; + /* We iterate through the linked list when it's all we have. + But continuing from an offset is slow that way. So when + DWFL->lookup_module is populated, we can instead keep our + place by jumping directly into the array. Since the actions + of a callback could cause it to get populated, we must + choose the style of place-holder when we return an offset, + and we encode the choice in the low bits of that value. */ + + Dwfl_Module *m = dwfl->modulelist; - while ((size_t) offset < dwfl->nmodules) + if ((offset & 3) == 1) { - Dwfl_Module *mod = dwfl->modules[offset++]; - if ((*callback) (MODCB_ARGS (mod), arg) != DWARF_CB_OK) - return offset; + offset >>= 2; + for (ptrdiff_t pos = 0; pos < offset; ++pos) + if (m == NULL) + return -1; + else + m = m->next; } + else if (((offset & 3) == 2) && likely (dwfl->lookup_module != NULL)) + { + offset >>= 2; + if ((size_t) offset - 1 == dwfl->lookup_elts) + return 0; + + if (unlikely ((size_t) offset - 1 > dwfl->lookup_elts)) + return -1; + + m = dwfl->lookup_module[offset - 1]; + if (unlikely (m == NULL)) + return -1; + } + else if (offset != 0) + { + __libdwfl_seterrno (DWFL_E_BADSTROFF); + return -1; + } + + while (m != NULL) + { + int ok = (*callback) (MODCB_ARGS (m), arg); + ++offset; + m = m->next; + if (ok != DWARF_CB_OK) + return ((dwfl->lookup_module == NULL) ? ((offset << 2) | 1) + : (((m == NULL ? (ptrdiff_t) dwfl->lookup_elts + 1 + : m->segment + 1) << 2) | 2)); + } return 0; } +INTDEF (dwfl_getmodules) |