Squashed 'third_party/elfutils/' content from commit 555e15e
Change-Id: I61cde98949e47e5c8c09c33260de17f30921be79
git-subtree-dir: third_party/elfutils
git-subtree-split: 555e15ebe8bf1eb33d00747173cfc80cc65648a4
diff --git a/libdwfl/segment.c b/libdwfl/segment.c
new file mode 100644
index 0000000..d9599a7
--- /dev/null
+++ b/libdwfl/segment.c
@@ -0,0 +1,337 @@
+/* Manage address space lookup table for libdwfl.
+ Copyright (C) 2008, 2009, 2010, 2013, 2015 Red Hat, Inc.
+ This file is part of elfutils.
+
+ This file is free software; you can redistribute it and/or modify
+ it under the terms of either
+
+ * the GNU Lesser General Public License as published by the Free
+ Software Foundation; either version 3 of the License, or (at
+ your option) any later version
+
+ or
+
+ * the GNU General Public License as published by the Free
+ Software Foundation; either version 2 of the License, or (at
+ your option) any later version
+
+ or both in parallel, as here.
+
+ elfutils 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 copies of the GNU General Public License and
+ the GNU Lesser General Public License along with this program. If
+ not, see <http://www.gnu.org/licenses/>. */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include "libdwflP.h"
+
+GElf_Addr
+internal_function
+__libdwfl_segment_start (Dwfl *dwfl, GElf_Addr start)
+{
+ if (dwfl->segment_align > 1)
+ start &= -dwfl->segment_align;
+ return start;
+}
+
+GElf_Addr
+internal_function
+__libdwfl_segment_end (Dwfl *dwfl, GElf_Addr end)
+{
+ if (dwfl->segment_align > 1)
+ end = (end + dwfl->segment_align - 1) & -dwfl->segment_align;
+ return end;
+}
+
+static bool
+insert (Dwfl *dwfl, size_t i, GElf_Addr start, GElf_Addr end, int segndx)
+{
+ bool need_start = (i == 0 || dwfl->lookup_addr[i - 1] != start);
+ bool need_end = (i + 1 >= dwfl->lookup_elts
+ || dwfl->lookup_addr[i + 1] != end);
+ size_t need = need_start + need_end;
+ if (need == 0)
+ return false;
+
+ if (dwfl->lookup_alloc - dwfl->lookup_elts < need)
+ {
+ size_t n = dwfl->lookup_alloc == 0 ? 16 : dwfl->lookup_alloc * 2;
+ GElf_Addr *naddr = realloc (dwfl->lookup_addr, sizeof naddr[0] * n);
+ if (unlikely (naddr == NULL))
+ return true;
+ int *nsegndx = realloc (dwfl->lookup_segndx, sizeof nsegndx[0] * n);
+ if (unlikely (nsegndx == NULL))
+ {
+ if (naddr != dwfl->lookup_addr)
+ free (naddr);
+ return true;
+ }
+ dwfl->lookup_alloc = n;
+ dwfl->lookup_addr = naddr;
+ dwfl->lookup_segndx = nsegndx;
+
+ if (dwfl->lookup_module != NULL)
+ {
+ /* Make sure this array is big enough too. */
+ Dwfl_Module **old = dwfl->lookup_module;
+ dwfl->lookup_module = realloc (dwfl->lookup_module,
+ sizeof dwfl->lookup_module[0] * n);
+ if (unlikely (dwfl->lookup_module == NULL))
+ {
+ free (old);
+ return true;
+ }
+ }
+ }
+
+ if (unlikely (i < dwfl->lookup_elts))
+ {
+ const size_t move = dwfl->lookup_elts - i;
+ memmove (&dwfl->lookup_addr[i + need], &dwfl->lookup_addr[i],
+ move * sizeof dwfl->lookup_addr[0]);
+ memmove (&dwfl->lookup_segndx[i + need], &dwfl->lookup_segndx[i],
+ move * sizeof dwfl->lookup_segndx[0]);
+ if (dwfl->lookup_module != NULL)
+ memmove (&dwfl->lookup_module[i + need], &dwfl->lookup_module[i],
+ move * sizeof dwfl->lookup_module[0]);
+ }
+
+ if (need_start)
+ {
+ dwfl->lookup_addr[i] = start;
+ dwfl->lookup_segndx[i] = segndx;
+ if (dwfl->lookup_module != NULL)
+ dwfl->lookup_module[i] = NULL;
+ ++i;
+ }
+ else
+ dwfl->lookup_segndx[i - 1] = segndx;
+
+ if (need_end)
+ {
+ dwfl->lookup_addr[i] = end;
+ dwfl->lookup_segndx[i] = -1;
+ if (dwfl->lookup_module != NULL)
+ dwfl->lookup_module[i] = NULL;
+ }
+
+ dwfl->lookup_elts += need;
+
+ return false;
+}
+
+static int
+lookup (Dwfl *dwfl, GElf_Addr address, int hint)
+{
+ if (hint >= 0
+ && address >= dwfl->lookup_addr[hint]
+ && ((size_t) hint + 1 == dwfl->lookup_elts
+ || address < dwfl->lookup_addr[hint + 1]))
+ return hint;
+
+ /* Do binary search on the array indexed by module load address. */
+ size_t l = 0, u = dwfl->lookup_elts;
+ while (l < u)
+ {
+ size_t idx = (l + u) / 2;
+ if (address < dwfl->lookup_addr[idx])
+ u = idx;
+ else
+ {
+ l = idx + 1;
+ if (l == dwfl->lookup_elts || address < dwfl->lookup_addr[l])
+ return idx;
+ }
+ }
+
+ return -1;
+}
+
+static bool
+reify_segments (Dwfl *dwfl)
+{
+ int hint = -1;
+ int highest = -1;
+ bool fixup = false;
+ for (Dwfl_Module *mod = dwfl->modulelist; mod != NULL; mod = mod->next)
+ if (! mod->gc)
+ {
+ const GElf_Addr start = __libdwfl_segment_start (dwfl, mod->low_addr);
+ const GElf_Addr end = __libdwfl_segment_end (dwfl, mod->high_addr);
+ bool resized = false;
+
+ int idx = lookup (dwfl, start, hint);
+ if (unlikely (idx < 0))
+ {
+ /* Module starts below any segment. Insert a low one. */
+ if (unlikely (insert (dwfl, 0, start, end, -1)))
+ return true;
+ idx = 0;
+ resized = true;
+ }
+ else if (dwfl->lookup_addr[idx] > start)
+ {
+ /* The module starts in the middle of this segment. Split it. */
+ if (unlikely (insert (dwfl, idx + 1, start, end,
+ dwfl->lookup_segndx[idx])))
+ return true;
+ ++idx;
+ resized = true;
+ }
+ else if (dwfl->lookup_addr[idx] < start)
+ {
+ /* The module starts past the end of this segment.
+ Add a new one. */
+ if (unlikely (insert (dwfl, idx + 1, start, end, -1)))
+ return true;
+ ++idx;
+ resized = true;
+ }
+
+ if ((size_t) idx + 1 < dwfl->lookup_elts
+ && end < dwfl->lookup_addr[idx + 1])
+ {
+ /* The module ends in the middle of this segment. Split it. */
+ if (unlikely (insert (dwfl, idx + 1,
+ end, dwfl->lookup_addr[idx + 1], -1)))
+ return true;
+ resized = true;
+ }
+
+ if (dwfl->lookup_module == NULL)
+ {
+ dwfl->lookup_module = calloc (dwfl->lookup_alloc,
+ sizeof dwfl->lookup_module[0]);
+ if (unlikely (dwfl->lookup_module == NULL))
+ return true;
+ }
+
+ /* Cache a backpointer in the module. */
+ mod->segment = idx;
+
+ /* Put MOD in the table for each segment that's inside it. */
+ do
+ dwfl->lookup_module[idx++] = mod;
+ while ((size_t) idx < dwfl->lookup_elts
+ && dwfl->lookup_addr[idx] < end);
+ assert (dwfl->lookup_module[mod->segment] == mod);
+
+ if (resized && idx - 1 >= highest)
+ /* Expanding the lookup tables invalidated backpointers
+ we've already stored. Reset those ones. */
+ fixup = true;
+
+ highest = idx - 1;
+ hint = (size_t) idx < dwfl->lookup_elts ? idx : -1;
+ }
+
+ if (fixup)
+ /* Reset backpointer indices invalidated by table insertions. */
+ for (size_t idx = 0; idx < dwfl->lookup_elts; ++idx)
+ if (dwfl->lookup_module[idx] != NULL)
+ dwfl->lookup_module[idx]->segment = idx;
+
+ return false;
+}
+
+int
+dwfl_addrsegment (Dwfl *dwfl, Dwarf_Addr address, Dwfl_Module **mod)
+{
+ if (unlikely (dwfl == NULL))
+ return -1;
+
+ if (unlikely (dwfl->lookup_module == NULL)
+ && mod != NULL
+ && unlikely (reify_segments (dwfl)))
+ {
+ __libdwfl_seterrno (DWFL_E_NOMEM);
+ return -1;
+ }
+
+ int idx = lookup (dwfl, address, -1);
+ if (likely (mod != NULL))
+ {
+ if (unlikely (idx < 0) || unlikely (dwfl->lookup_module == NULL))
+ *mod = NULL;
+ else
+ {
+ *mod = dwfl->lookup_module[idx];
+
+ /* If this segment does not have a module, but the address is
+ the upper boundary of the previous segment's module, use that. */
+ if (*mod == NULL && idx > 0 && dwfl->lookup_addr[idx] == address)
+ {
+ *mod = dwfl->lookup_module[idx - 1];
+ if (*mod != NULL && (*mod)->high_addr != address)
+ *mod = NULL;
+ }
+ }
+ }
+
+ if (likely (idx >= 0))
+ /* Translate internal segment table index to user segment index. */
+ idx = dwfl->lookup_segndx[idx];
+
+ return idx;
+}
+INTDEF (dwfl_addrsegment)
+
+int
+dwfl_report_segment (Dwfl *dwfl, int ndx, const GElf_Phdr *phdr, GElf_Addr bias,
+ const void *ident)
+{
+ if (dwfl == NULL)
+ return -1;
+
+ if (ndx < 0)
+ ndx = dwfl->lookup_tail_ndx;
+
+ if (phdr->p_align > 1 && (dwfl->segment_align <= 1 ||
+ phdr->p_align < dwfl->segment_align))
+ dwfl->segment_align = phdr->p_align;
+
+ if (unlikely (dwfl->lookup_module != NULL))
+ {
+ free (dwfl->lookup_module);
+ dwfl->lookup_module = NULL;
+ }
+
+ GElf_Addr start = __libdwfl_segment_start (dwfl, bias + phdr->p_vaddr);
+ GElf_Addr end = __libdwfl_segment_end (dwfl,
+ bias + phdr->p_vaddr + phdr->p_memsz);
+
+ /* Coalesce into the last one if contiguous and matching. */
+ if (ndx != dwfl->lookup_tail_ndx
+ || ident == NULL
+ || ident != dwfl->lookup_tail_ident
+ || start != dwfl->lookup_tail_vaddr
+ || phdr->p_offset != dwfl->lookup_tail_offset)
+ {
+ /* Normally just appending keeps us sorted. */
+
+ size_t i = dwfl->lookup_elts;
+ while (i > 0 && unlikely (start < dwfl->lookup_addr[i - 1]))
+ --i;
+
+ if (unlikely (insert (dwfl, i, start, end, ndx)))
+ {
+ __libdwfl_seterrno (DWFL_E_NOMEM);
+ return -1;
+ }
+ }
+
+ dwfl->lookup_tail_ident = ident;
+ dwfl->lookup_tail_vaddr = end;
+ dwfl->lookup_tail_offset = end - bias - phdr->p_vaddr + phdr->p_offset;
+ dwfl->lookup_tail_ndx = ndx + 1;
+
+ return ndx;
+}
+INTDEF (dwfl_report_segment)