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Diffstat (limited to 'elf')
-rw-r--r--elf/sprof.c176
1 files changed, 132 insertions, 44 deletions
diff --git a/elf/sprof.c b/elf/sprof.c
index 1a4b068..afe3955 100644
--- a/elf/sprof.c
+++ b/elf/sprof.c
@@ -48,14 +48,18 @@
#include <endian.h>
#if BYTE_ORDER == BIG_ENDIAN
-#define byteorder ELFDATA2MSB
-#define byteorder_name "big-endian"
+# define byteorder ELFDATA2MSB
+# define byteorder_name "big-endian"
#elif BYTE_ORDER == LITTLE_ENDIAN
-#define byteorder ELFDATA2LSB
-#define byteorder_name "little-endian"
+# define byteorder ELFDATA2LSB
+# define byteorder_name "little-endian"
#else
-#error "Unknown BYTE_ORDER " BYTE_ORDER
-#define byteorder ELFDATANONE
+# error "Unknown BYTE_ORDER " BYTE_ORDER
+# define byteorder ELFDATANONE
+#endif
+
+#ifndef PATH_MAX
+# define PATH_MAX 1024
#endif
@@ -82,7 +86,9 @@ static const struct argp_option options[] =
};
/* Short description of program. */
-static const char doc[] = N_("Read and display shared object profiling data");
+static const char doc[] = N_("Read and display shared object profiling data.\v\
+For bug reporting instructions, please see:\n\
+<http://www.gnu.org/software/libc/bugs.html>.\n");
/* Strings for arguments in help texts. */
static const char args_doc[] = N_("SHOBJ [PROFDATA]");
@@ -93,7 +99,7 @@ static error_t parse_opt (int key, char *arg, struct argp_state *state);
/* Data structure to communicate with argp functions. */
static struct argp argp =
{
- options, parse_opt, args_doc, doc, NULL, NULL
+ options, parse_opt, args_doc, doc
};
@@ -108,11 +114,8 @@ static enum
DEFAULT_MODE = FLAT_MODE | CALL_GRAPH_MODE
} mode;
-/* If nonzero the total number of invocations of a function is emitted. */
-int count_total;
-
/* Nozero for testing. */
-int do_test;
+static int do_test;
/* Strcuture describing calls. */
struct here_fromstruct
@@ -204,7 +207,7 @@ struct profdata
};
/* Search tree for symbols. */
-void *symroot;
+static void *symroot;
static struct known_symbol **sortsym;
static size_t symidx;
static uintmax_t total_ticks;
@@ -374,11 +377,7 @@ load_shobj (const char *name)
ElfW(Ehdr) *ehdr;
int fd;
ElfW(Shdr) *shdr;
- void *ptr;
size_t pagesize = getpagesize ();
- const char *shstrtab;
- int idx;
- ElfW(Shdr) *symtab_entry;
/* Since we use dlopen() we must be prepared to work around the sometimes
strange lookup rules for the shared objects. If we have a file foo.so
@@ -529,39 +528,131 @@ load_shobj (const char *name)
error (EXIT_FAILURE, errno, _("Reopening shared object `%s' failed"),
map->l_name);
- /* Now map the section header. */
- ptr = mmap (NULL, (ehdr->e_shnum * sizeof (ElfW(Shdr))
- + (ehdr->e_shoff & (pagesize - 1))), PROT_READ,
- MAP_SHARED|MAP_FILE, fd, ehdr->e_shoff & ~(pagesize - 1));
- if (ptr == MAP_FAILED)
- error (EXIT_FAILURE, errno, _("mapping of section headers failed"));
- shdr = (ElfW(Shdr) *) ((char *) ptr + (ehdr->e_shoff & (pagesize - 1)));
+ /* Map the section header. */
+ size_t size = ehdr->e_shnum * sizeof (ElfW(Shdr));
+ shdr = (ElfW(Shdr) *) alloca (size);
+ if (pread (fd, shdr, size, ehdr->e_shoff) != size)
+ error (EXIT_FAILURE, errno, _("reading of section headers failed"));
/* Get the section header string table. */
- ptr = mmap (NULL, (shdr[ehdr->e_shstrndx].sh_size
- + (shdr[ehdr->e_shstrndx].sh_offset & (pagesize - 1))),
- PROT_READ, MAP_SHARED|MAP_FILE, fd,
- shdr[ehdr->e_shstrndx].sh_offset & ~(pagesize - 1));
- if (ptr == MAP_FAILED)
+ char *shstrtab = (char *) alloca (shdr[ehdr->e_shstrndx].sh_size);
+ if (pread (fd, shstrtab, shdr[ehdr->e_shstrndx].sh_size,
+ shdr[ehdr->e_shstrndx].sh_offset)
+ != shdr[ehdr->e_shstrndx].sh_size)
error (EXIT_FAILURE, errno,
- _("mapping of section header string table failed"));
- shstrtab = ((const char *) ptr
- + (shdr[ehdr->e_shstrndx].sh_offset & (pagesize - 1)));
+ _("reading of section header string table failed"));
/* Search for the ".symtab" section. */
- symtab_entry = NULL;
- for (idx = 0; idx < ehdr->e_shnum; ++idx)
+ ElfW(Shdr) *symtab_entry = NULL;
+ ElfW(Shdr) *debuglink_entry = NULL;
+ for (int idx = 0; idx < ehdr->e_shnum; ++idx)
if (shdr[idx].sh_type == SHT_SYMTAB
&& strcmp (shstrtab + shdr[idx].sh_name, ".symtab") == 0)
{
symtab_entry = &shdr[idx];
break;
}
+ else if (shdr[idx].sh_type == SHT_PROGBITS
+ && strcmp (shstrtab + shdr[idx].sh_name, ".gnu_debuglink") == 0)
+ debuglink_entry = &shdr[idx];
- /* We don't need the section header string table anymore. */
- munmap (ptr, (shdr[ehdr->e_shstrndx].sh_size
- + (shdr[ehdr->e_shstrndx].sh_offset & (pagesize - 1))));
+ /* Get the file name of the debuginfo file if necessary. */
+ int symfd = fd;
+ if (symtab_entry == NULL && debuglink_entry != NULL)
+ {
+ size_t size = debuglink_entry->sh_size;
+ char *debuginfo_fname = (char *) alloca (size + 1);
+ debuginfo_fname[size] = '\0';
+ if (pread (fd, debuginfo_fname, size, debuglink_entry->sh_offset)
+ != size)
+ {
+ fprintf (stderr, _("*** Cannot read debuginfo file name: %m\n"));
+ goto no_debuginfo;
+ }
+ static const char procpath[] = "/proc/self/fd/%d";
+ char origprocname[sizeof (procpath) + sizeof (int) * 3];
+ snprintf (origprocname, sizeof (origprocname), procpath, fd);
+ char *origlink = (char *) alloca (PATH_MAX + 1);
+ origlink[PATH_MAX] = '\0';
+ if (readlink (origprocname, origlink, PATH_MAX) == -1)
+ goto no_debuginfo;
+
+ /* Try to find the actual file. There are three places:
+ 1. the same directory the DSO is in
+ 2. in a subdir named .debug of the directory the DSO is in
+ 3. in /usr/lib/debug/PATH-OF-DSO
+ */
+ char *realname = canonicalize_file_name (origlink);
+ char *cp = NULL;
+ if (realname == NULL || (cp = strrchr (realname, '/')) == NULL)
+ error (EXIT_FAILURE, errno, _("cannot determine file name"));
+
+ /* Leave the last slash in place. */
+ *++cp = '\0';
+
+ /* First add the debuginfo file name only. */
+ static const char usrlibdebug[]= "/usr/lib/debug/";
+ char *workbuf = (char *) alloca (sizeof (usrlibdebug)
+ + (cp - realname)
+ + strlen (debuginfo_fname));
+ strcpy (stpcpy (workbuf, realname), debuginfo_fname);
+
+ int fd2 = open (workbuf, O_RDONLY);
+ if (fd2 == -1)
+ {
+ strcpy (stpcpy (stpcpy (workbuf, realname), ".debug/"),
+ debuginfo_fname);
+ fd2 = open (workbuf, O_RDONLY);
+ if (fd2 == -1)
+ {
+ strcpy (stpcpy (stpcpy (workbuf, usrlibdebug), realname),
+ debuginfo_fname);
+ fd2 = open (workbuf, O_RDONLY);
+ }
+ }
+
+ if (fd2 != -1)
+ {
+ ElfW(Ehdr) ehdr2;
+
+ /* Read the ELF header. */
+ if (pread (fd2, &ehdr2, sizeof (ehdr2), 0) != sizeof (ehdr2))
+ error (EXIT_FAILURE, errno,
+ _("reading of ELF header failed"));
+
+ /* Map the section header. */
+ size_t size = ehdr2.e_shnum * sizeof (ElfW(Shdr));
+ ElfW(Shdr) *shdr2 = (ElfW(Shdr) *) alloca (size);
+ if (pread (fd2, shdr2, size, ehdr2.e_shoff) != size)
+ error (EXIT_FAILURE, errno,
+ _("reading of section headers failed"));
+
+ /* Get the section header string table. */
+ shstrtab = (char *) alloca (shdr2[ehdr2.e_shstrndx].sh_size);
+ if (pread (fd2, shstrtab, shdr2[ehdr2.e_shstrndx].sh_size,
+ shdr2[ehdr2.e_shstrndx].sh_offset)
+ != shdr2[ehdr2.e_shstrndx].sh_size)
+ error (EXIT_FAILURE, errno,
+ _("reading of section header string table failed"));
+
+ /* Search for the ".symtab" section. */
+ for (int idx = 0; idx < ehdr2.e_shnum; ++idx)
+ if (shdr2[idx].sh_type == SHT_SYMTAB
+ && strcmp (shstrtab + shdr2[idx].sh_name, ".symtab") == 0)
+ {
+ symtab_entry = &shdr2[idx];
+ shdr = shdr2;
+ symfd = fd2;
+ break;
+ }
+
+ if (fd2 != symfd)
+ close (fd2);
+ }
+ }
+
+ no_debuginfo:
if (symtab_entry == NULL)
{
fprintf (stderr, _("\
@@ -591,9 +682,9 @@ load_shobj (const char *name)
}
result->symbol_map = mmap (NULL, max_offset - min_offset,
- PROT_READ, MAP_SHARED|MAP_FILE, fd,
+ PROT_READ, MAP_SHARED|MAP_FILE, symfd,
min_offset);
- if (result->symbol_map == NULL)
+ if (result->symbol_map == MAP_FAILED)
error (EXIT_FAILURE, errno, _("failed to load symbol data"));
result->symtab
@@ -605,13 +696,10 @@ load_shobj (const char *name)
result->symbol_mapsize = max_offset - min_offset;
}
- /* Now we also don't need the section header table anymore. */
- munmap ((char *) shdr - (ehdr->e_shoff & (pagesize - 1)),
- (ehdr->e_phnum * sizeof (ElfW(Shdr))
- + (ehdr->e_shoff & (pagesize - 1))));
-
/* Free the descriptor for the shared object. */
close (fd);
+ if (symfd != fd)
+ close (symfd);
return result;
}
generated by cgit v1.1 at 2024-12-23 05:36:57 +0000