/* We already read the ELF header. We have to copy the header
since we possibly modify the data here and the caller
expects the memory it passes in to be preserved. */
- ehdr.p = memcpy (&ehdr_mem, e_ident,
- is32 ? sizeof (Elf32_Ehdr) : sizeof (Elf64_Ehdr));
+ ehdr.p = &ehdr_mem;
if (is32)
{
- CONVERT (ehdr.e32->e_shnum);
- CONVERT (ehdr.e32->e_shoff);
+ if (ALLOW_UNALIGNED)
+ {
+ ehdr_mem.e32.e_shnum = ((Elf32_Ehdr *) e_ident)->e_shnum;
+ ehdr_mem.e32.e_shoff = ((Elf32_Ehdr *) e_ident)->e_shoff;
+ }
+ else
+ memcpy (&ehdr_mem, e_ident, sizeof (Elf32_Ehdr));
+
+ CONVERT (ehdr_mem.e32.e_shnum);
+ CONVERT (ehdr_mem.e32.e_shoff);
}
else
{
- CONVERT (ehdr.e64->e_shnum);
- CONVERT (ehdr.e64->e_shoff);
+ if (ALLOW_UNALIGNED)
+ {
+ ehdr_mem.e64.e_shnum = ((Elf64_Ehdr *) e_ident)->e_shnum;
+ ehdr_mem.e64.e_shoff = ((Elf64_Ehdr *) e_ident)->e_shoff;
+ }
+ else
+ memcpy (&ehdr_mem, e_ident, sizeof (Elf64_Ehdr));
+
+ CONVERT (ehdr_mem.e64.e_shnum);
+ CONVERT (ehdr_mem.e64.e_shoff);
}
}
off_t offset, size_t maxsize, Elf_Cmd cmd, Elf *parent)
{
/* Verify the binary is of the class we can handle. */
- if ((e_ident[EI_CLASS] != ELFCLASS32
- && e_ident[EI_CLASS] != ELFCLASS64)
- /* We also can only handle two encodings. */
- || (e_ident[EI_DATA] != ELFDATA2LSB
- && e_ident[EI_DATA] != ELFDATA2MSB))
+ if (unlikely ((e_ident[EI_CLASS] != ELFCLASS32
+ && e_ident[EI_CLASS] != ELFCLASS64)
+ /* We also can only handle two encodings. */
+ || (e_ident[EI_DATA] != ELFDATA2LSB
+ && e_ident[EI_DATA] != ELFDATA2MSB)))
{
/* Cannot handle this. */
__libelf_seterrno (ELF_E_INVALID_FILE);
/* Some more or less arbitrary value. */
elf->state.elf.scnincr = 10;
+ /* Make the class easily available. */
+ elf->class = e_ident[EI_CLASS];
+
if (e_ident[EI_CLASS] == ELFCLASS32)
{
/* This pointer might not be directly usable if the alignment is
& (__alignof__ (Elf32_Phdr) - 1)) == 0)))
{
/* We can use the mmapped memory. */
- elf->state.elf32.ehdr =
- (Elf32_Ehdr *) ((char *) map_address + offset);
- elf->state.elf32.shdr =
- (Elf32_Shdr *) ((char *) map_address + offset
- + elf->state.elf32.ehdr->e_shoff);
- if (elf->state.elf32.ehdr->e_phnum)
+ elf->state.elf32.ehdr = ehdr;
+ elf->state.elf32.shdr
+ = (Elf32_Shdr *) ((char *) ehdr + ehdr->e_shoff);
+ if (ehdr->e_phnum > 0)
/* Assign a value only if there really is a program
header. Otherwise the value remains NULL. */
elf->state.elf32.phdr
- = (Elf32_Phdr *) ((char *) map_address + offset
- + elf->state.elf32.ehdr->e_phoff);
+ = (Elf32_Phdr *) ((char *) ehdr + ehdr->e_phoff);
for (size_t cnt = 0; cnt < scncnt; ++cnt)
{
}
else
{
- if (likely (map_address != NULL))
- /* Copy the data. */
- memcpy (&elf->state.elf32.ehdr_mem,
- (char *) map_address + offset, sizeof (Elf32_Ehdr));
- else
- /* Copy the data. */
- memcpy (&elf->state.elf32.ehdr_mem, e_ident, sizeof (Elf32_Ehdr));
+ /* Copy the ELF header. */
+ elf->state.elf32.ehdr = memcpy (&elf->state.elf32.ehdr_mem, e_ident,
+ sizeof (Elf32_Ehdr));
if (e_ident[EI_DATA] != MY_ELFDATA)
{
CONVERT (elf->state.elf32.ehdr_mem.e_shstrndx);
}
- elf->state.elf32.ehdr = &elf->state.elf32.ehdr_mem;
-
for (size_t cnt = 0; cnt < scncnt; ++cnt)
{
elf->state.elf32.scns.data[cnt].index = cnt;
& (__alignof__ (Elf64_Phdr) - 1)) == 0)))
{
/* We can use the mmapped memory. */
- elf->state.elf64.ehdr =
- (Elf64_Ehdr *) ((char *) map_address + offset);
- elf->state.elf64.shdr =
- (Elf64_Shdr *) ((char *) map_address + offset
- + elf->state.elf64.ehdr->e_shoff);
- if (elf->state.elf64.ehdr->e_phnum)
+ elf->state.elf64.ehdr = ehdr;
+ elf->state.elf64.shdr
+ = (Elf64_Shdr *) ((char *) ehdr + ehdr->e_shoff);
+ if (ehdr->e_phnum > 0)
/* Assign a value only if there really is a program
header. Otherwise the value remains NULL. */
elf->state.elf64.phdr
- = (Elf64_Phdr *) ((char *) map_address + offset
- + elf->state.elf64.ehdr->e_phoff);
+ = (Elf64_Phdr *) ((char *) ehdr + ehdr->e_phoff);
for (size_t cnt = 0; cnt < scncnt; ++cnt)
{
}
else
{
- if (likely (map_address != NULL))
- /* Copy the data. */
- memcpy (&elf->state.elf64.ehdr_mem,
- (char *) map_address + offset, sizeof (Elf64_Ehdr));
- else
- /* Copy the data. */
- memcpy (&elf->state.elf64.ehdr_mem, e_ident, sizeof (Elf64_Ehdr));
+ /* Copy the ELF header. */
+ elf->state.elf64.ehdr = memcpy (&elf->state.elf64.ehdr_mem, e_ident,
+ sizeof (Elf64_Ehdr));
if (e_ident[EI_DATA] != MY_ELFDATA)
{
CONVERT (elf->state.elf64.ehdr_mem.e_shstrndx);
}
- elf->state.elf64.ehdr = &elf->state.elf64.ehdr_mem;
-
for (size_t cnt = 0; cnt < scncnt; ++cnt)
{
elf->state.elf64.scns.data[cnt].index = cnt;
elf->state.elf64.scns_last = &elf->state.elf64.scns;
}
- /* Make the class easily available. */
- elf->class = e_ident[EI_CLASS];
-
return elf;
}
--- /dev/null
+/* Print the strings of printable characters in files.
+ Copyright (C) 2005 Red Hat, Inc.
+ Written by Ulrich Drepper <drepper@redhat.com>, 2005.
+
+ This program is Open Source software; you can redistribute it and/or
+ modify it under the terms of the Open Software License version 1.0 as
+ published by the Open Source Initiative.
+
+ You should have received a copy of the Open Software License along
+ with this program; if not, you may obtain a copy of the Open Software
+ License version 1.0 from http://www.opensource.org/licenses/osl.php or
+ by writing the Open Source Initiative c/o Lawrence Rosen, Esq.,
+ 3001 King Ranch Road, Ukiah, CA 95482. */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <argp.h>
+#include <assert.h>
+#include <ctype.h>
+#include <endian.h>
+#include <errno.h>
+#include <error.h>
+#include <fcntl.h>
+#include <gelf.h>
+#include <inttypes.h>
+#include <libintl.h>
+#include <locale.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdio_ext.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/mman.h>
+#include <sys/param.h>
+#include <sys/stat.h>
+
+#include <system.h>
+
+
+/* Prototypes of local functions. */
+static int read_fd (int fd, const char *fname, off64_t fdlen);
+static int read_elf (Elf *elf, int fd, const char *fname, off64_t fdlen);
+
+
+/* Name and version of program. */
+static void print_version (FILE *stream, struct argp_state *state);
+void (*argp_program_version_hook) (FILE *, struct argp_state *) = print_version;
+
+/* Bug report address. */
+const char *argp_program_bug_address = PACKAGE_BUGREPORT;
+
+/* Definitions of arguments for argp functions. */
+static const struct argp_option options[] =
+{
+ { NULL, 0, NULL, 0, N_("Output Selection:"), 0 },
+ { "all", 'a', NULL, 0, N_("Scan entire file, not only loaded sections"), 0 },
+ { "bytes", 'n', "MIN-LEN", 0,
+ N_("Only NUL-terminated sequences of MIN-LEN characters or more are printed"), 0 },
+ { "encoding", 'e', "SELECTOR", 0, N_("\
+Select character size and endianess: s = 7-bit, S = 8-bit, {b,l} = 16-bit, {B,L} = 32-bit"),
+ 0},
+ { "print-file-name", 'f', NULL, 0,
+ N_("Print name of the file before each string."), 0 },
+ { "radix", 't', "{o,d,x}", 0,
+ N_("Print location of the string in base 8, 10, or 16 respectively."), 0 },
+ { NULL, 'o', NULL, 0, N_("Alias for --radix=o"), 0 },
+
+ { NULL, 0, NULL, 0, N_("Miscellaneous:"), 0 },
+ { NULL, 0, NULL, 0, NULL, 0 }
+};
+
+/* Short description of program. */
+static const char doc[] = N_("\
+Print the strings of printable characters in files.");
+
+/* Strings for arguments in help texts. */
+static const char args_doc[] = N_("[FILE...]");
+
+/* Prototype for option handler. */
+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, NULL
+};
+
+
+/* Global variables. */
+
+/* True if whole file and not only loaded sections are looked at. */
+static bool entire_file;
+
+/* Minimum length of any sequence reported. */
+static size_t min_len = 4;
+
+/* Number of bytes per character. */
+static size_t bytes_per_char = 1;
+
+/* Minimum length of any sequence reported in bytes. */
+static size_t min_len_bytes;
+
+/* True if multibyte characters are in big-endian order. */
+static bool big_endian;
+
+/* True unless 7-bit ASCII are expected. */
+static bool char_7bit;
+
+/* True if file names should be printed before strings. */
+static bool print_file_name;
+
+/* Location print format string. */
+static const char *locfmt;
+
+/* Page size in use. */
+static size_t ps;
+
+
+/* Mapped parts of the ELF file. */
+static unsigned char *elfmap;
+static unsigned char *elfmap_base;
+static size_t elfmap_size;
+static off64_t elfmap_off;
+
+
+int
+main (int argc, char *argv[])
+{
+ /* We use no threads. */
+ __fsetlocking (stdin, FSETLOCKING_BYCALLER);
+ __fsetlocking (stdout, FSETLOCKING_BYCALLER);
+
+ /* Set locale. */
+ (void) setlocale (LC_ALL, "");
+
+ /* Make sure the message catalog can be found. */
+ (void) bindtextdomain (PACKAGE, LOCALEDIR);
+
+ /* Initialize the message catalog. */
+ (void) textdomain (PACKAGE);
+
+ /* Parse and process arguments. */
+ int remaining;
+ (void) argp_parse (&argp, argc, argv, 0, &remaining, NULL);
+
+ /* Tell the library which version we are expecting. */
+ elf_version (EV_CURRENT);
+
+ /* Determine the page size. We will likely need it a couple of times. */
+ ps = sysconf (_SC_PAGESIZE);
+
+ struct stat64 st;
+ int result = 0;
+ if (remaining == argc)
+ /* We read from standard input. This we cannot do for a
+ structured file. */
+ result = read_fd (STDOUT_FILENO,
+ print_file_name ? "{standard input}" : NULL,
+ fstat64 (STDOUT_FILENO, &st) == 0
+ ? st.st_size : INT64_C (0x7fffffffffffffff));
+ else
+ do
+ {
+ int fd = (strcmp (argv[remaining], "-") == 0
+ ? STDIN_FILENO : open (argv[remaining], O_RDONLY));
+ if (unlikely (fd == -1))
+ {
+ error (0, errno, gettext ("cannot open '%s'"), argv[remaining]);
+ result = 1;
+ }
+ else
+ {
+ const char *fname = print_file_name ? argv[remaining] : NULL;
+ int fstat_fail = fstat64 (fd, &st);
+ off64_t fdlen = (fstat_fail
+ ? INT64_C (0x7fffffffffffffff) : st.st_size);
+ if (fdlen > (off64_t) min_len_bytes)
+ {
+ Elf *elf = NULL;
+ if (entire_file
+ || fstat_fail
+ || !S_ISREG (st.st_mode)
+ || (elf = elf_begin (fd, ELF_C_READ, NULL)) == NULL
+ || elf_kind (elf) != ELF_K_ELF)
+ result |= read_fd (fd, fname, fdlen);
+ else
+ result |= read_elf (elf, fd, fname, fdlen);
+
+ /* This call will succeed even if ELF is NULL. */
+ elf_end (elf);
+ }
+
+ if (strcmp (argv[remaining], "-") != 0)
+ close (fd);
+ }
+
+ if (elfmap != NULL && elfmap != MAP_FAILED)
+ munmap (elfmap, elfmap_size);
+ }
+ while (++remaining < argc);
+
+ return result;
+}
+
+
+/* Print the version information. */
+static void
+print_version (FILE *stream, struct argp_state *state __attribute__ ((unused)))
+{
+ fprintf (stream, "strings (%s) %s\n", PACKAGE_NAME, VERSION);
+ fprintf (stream, gettext ("\
+Copyright (C) %s Red Hat, Inc.\n\
+This is free software; see the source for copying conditions. There is NO\n\
+warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n\
+"), "2005");
+ fprintf (stream, gettext ("Written by %s.\n"), "Ulrich Drepper");
+}
+
+
+/* Handle program arguments. */
+static error_t
+parse_opt (int key, char *arg,
+ struct argp_state *state __attribute__ ((unused)))
+{
+ switch (key)
+ {
+ case 'a':
+ entire_file = true;
+ break;
+
+ case 'e':
+ /* We expect a string of one character. */
+ switch (arg[1] != '\0' ? '\0' : arg[0])
+ {
+ case 's':
+ case 'S':
+ char_7bit = arg[0] == 's';
+ bytes_per_char = 1;
+ break;
+
+ case 'b':
+ case 'B':
+ big_endian = true;
+ /* FALLTHROUGH */
+
+ case 'l':
+ case 'L':
+ bytes_per_char = isupper (arg[0]) ? 4 : 2;
+ break;
+
+ default:
+ error (0, 0, gettext ("invalid value '%s' for %s parameter"),
+ arg, "-e");
+ argp_help (&argp, stderr, ARGP_HELP_SEE, "strings");
+ return ARGP_ERR_UNKNOWN;
+ }
+ break;
+
+ case 'f':
+ print_file_name = true;
+ break;
+
+ case 'n':
+ min_len = atoi (arg);
+ break;
+
+ case 'o':
+ goto octfmt;
+
+ case 't':
+ switch (arg[0])
+ {
+ case 'd':
+ locfmt = "%7" PRId64 " ";
+ break;
+
+ case 'o':
+ octfmt:
+ locfmt = "%7" PRIo64 " ";
+ break;
+
+ case 'x':
+ locfmt = "%7" PRIx64 " ";
+ break;
+
+ default:
+ error (0, 0, gettext ("invalid value '%s' for %s parameter"),
+ arg, "-t");
+ argp_help (&argp, stderr, ARGP_HELP_SEE, "strings");
+ return ARGP_ERR_UNKNOWN;
+ }
+ break;
+
+ case ARGP_KEY_FINI:
+ /* Compute the length in bytes of any match. */
+ if (min_len <= 0 || min_len > INT_MAX / bytes_per_char)
+ error (EXIT_FAILURE, 0,
+ gettext ("invalid minimum length of matched string size"));
+ min_len_bytes = min_len * bytes_per_char;
+ break;
+
+ default:
+ return ARGP_ERR_UNKNOWN;
+ }
+ return 0;
+}
+
+
+static void
+process_chunk_mb (const char *fname, const unsigned char *buf, off64_t to,
+ size_t len, char **unprinted)
+{
+ size_t curlen = *unprinted == NULL ? 0 : strlen (*unprinted);
+ const unsigned char *start = buf;
+ while (len >= bytes_per_char)
+ {
+ uint32_t ch;
+
+ if (bytes_per_char == 2)
+ {
+ if (big_endian)
+ ch = buf[0] << 8 | buf[1];
+ else
+ ch = buf[1] << 8 | buf[0];
+ }
+ else
+ {
+ if (big_endian)
+ ch = buf[0] << 24 | buf[1] << 16 | buf[2] << 8 | buf[3];
+ else
+ ch = buf[3] << 24 | buf[2] << 16 | buf[1] << 8 | buf[0];
+ }
+
+ if (ch <= 255 && (ch == '\t' || isprint (ch)))
+ {
+ ++buf;
+ ++curlen;
+ }
+ else
+ {
+ if (curlen >= min_len)
+ {
+ /* We found a match. */
+ if (unlikely (fname != NULL))
+ {
+ fputs_unlocked (fname, stdout);
+ fputs_unlocked (": ", stdout);
+ }
+
+ if (unlikely (locfmt != NULL))
+ printf (locfmt, (int64_t) to - len);
+
+ if (unlikely (*unprinted != NULL))
+ {
+ fputs_unlocked (*unprinted, stdout);
+ free (*unprinted);
+ *unprinted = NULL;
+ }
+
+ /* There is no sane way of printing the string. If we
+ assume the file data is encoded in UCS-2/UTF-16 or
+ UCS-4/UTF-32 respectively we could covert the string.
+ But there is no such guarantee. */
+ fwrite_unlocked (start, 1, buf - start, stdout);
+ putc_unlocked ('\n', stdout);
+ }
+
+ start = ++buf;
+ curlen = 0;
+
+ if (len <= min_len)
+ break;
+ }
+
+ --len;
+ }
+
+ if (curlen != 0)
+ *unprinted = xstrndup ((const char *) start, curlen);
+}
+
+
+static void
+process_chunk (const char *fname, const unsigned char *buf, off64_t to,
+ size_t len, char **unprinted)
+{
+ /* We are not going to slow the check down for the 2- and 4-byte
+ encodings. Handle them special. */
+ if (unlikely (bytes_per_char != 1))
+ {
+ process_chunk_mb (fname, buf, to, len, unprinted);
+ return;
+ }
+
+ size_t curlen = *unprinted == NULL ? 0 : strlen (*unprinted);
+ const unsigned char *start = buf;
+ while (len > 0)
+ {
+ if ((*buf == '\t' || isprint (*buf))
+ && (! char_7bit || *buf <= 127))
+ {
+ ++buf;
+ ++curlen;
+ }
+ else
+ {
+ if (curlen >= min_len)
+ {
+ /* We found a match. */
+ if (unlikely (fname != NULL))
+ {
+ fputs_unlocked (fname, stdout);
+ fputs_unlocked (": ", stdout);
+ }
+
+ if (unlikely (locfmt != NULL))
+ printf (locfmt, (int64_t) to - len);
+
+ if (unlikely (*unprinted != NULL))
+ {
+ fputs_unlocked (*unprinted, stdout);
+ free (*unprinted);
+ *unprinted = NULL;
+ }
+ fwrite_unlocked (start, 1, buf - start, stdout);
+ putc_unlocked ('\n', stdout);
+ }
+
+ start = ++buf;
+ curlen = 0;
+
+ if (len <= min_len)
+ break;
+ }
+
+ --len;
+ }
+
+ if (curlen != 0)
+ *unprinted = xstrndup ((const char *) start, curlen);
+}
+
+
+/* Map a file in as large chunks as possible. */
+static void *
+map_file (int fd, off64_t start_off, off64_t fdlen, size_t *map_sizep)
+{
+ /* Maximum size we mmap. We use an #ifdef to avoid overflows on
+ 32-bit machines. 64-bit machines these days do not have usable
+ address spaces larger than about 43 bits. Not that any file
+ should be that large. */
+#if SIZE_MAX > 0xffffffff
+ const size_t mmap_max = 0x4000000000lu;
+#else
+ const size_t mmap_max = 0x40000000lu;
+#endif
+
+ /* Try to mmap the file. */
+ size_t map_size = MIN ((off64_t) mmap_max, fdlen);
+ const size_t map_size_min = MAX (MAX (SIZE_MAX / 16, 2 * ps),
+ roundup (2 * min_len_bytes + 1, ps));
+ void *mem;
+ while (1)
+ {
+ /* We map the memory for reading only here. Since we will
+ always look at every byte of the file it makes sense to
+ use MAP_POPULATE. */
+ mem = mmap64 (NULL, map_size, PROT_READ, MAP_PRIVATE | MAP_POPULATE,
+ fd, start_off);
+ if (mem != MAP_FAILED)
+ {
+ /* We will go through the mapping sequentially. */
+ (void) posix_madvise (mem, map_size, POSIX_MADV_SEQUENTIAL);
+ break;
+ }
+ if (errno != EINVAL && errno != ENOMEM)
+ /* This is an error other than the lack of address space. */
+ break;
+
+ /* Maybe the size of the mapping is too big. Try again. */
+ map_size /= 2;
+ if (map_size < map_size_min)
+ /* That size should have fit. */
+ break;
+ }
+
+ *map_sizep = map_size;
+ return mem;
+}
+
+
+/* Read the file without mapping. */
+static int
+read_block_no_mmap (int fd, const char *fname, off64_t from, off64_t fdlen)
+{
+ char *unprinted = NULL;
+#define CHUNKSIZE 65536
+ unsigned char *buf = xmalloc (CHUNKSIZE + min_len_bytes
+ + bytes_per_char - 1);
+ size_t ntrailer = 0;
+ int result = 0;
+ while (fdlen > 0)
+ {
+ ssize_t n = TEMP_FAILURE_RETRY (read (fd, buf + ntrailer,
+ MIN (fdlen, CHUNKSIZE)));
+ if (n == 0)
+ {
+ /* There are less than MIN_LEN+1 bytes left so there cannot be
+ another match. */
+ assert (unprinted == NULL || ntrailer == 0);
+ break;
+ }
+ if (unlikely (n < 0))
+ {
+ /* Something went wrong. */
+ result = 1;
+ break;
+ }
+
+ /* Account for the number of bytes read in this round. */
+ fdlen -= n;
+
+ /* Do not use the signed N value. Note that the addition cannot
+ overflow. */
+ size_t nb = (size_t) n + ntrailer;
+ if (nb >= min_len_bytes)
+ {
+ /* We only use complete charactesr. */
+ nb &= ~(bytes_per_char - 1);
+
+ process_chunk (fname, buf, from + nb, nb, &unprinted);
+
+ /* If the last bytes of the buffer (module the character
+ size) have been printed we are not copying them. */
+ size_t to_keep = unprinted != NULL ? 0 : min_len_bytes;
+
+ memmove (buf, buf + nb - to_keep, to_keep + nb);
+ ntrailer = to_keep + nb;
+ from += nb;
+ }
+ else
+ ntrailer = nb;
+ }
+
+ free (buf);
+
+ /* Don't print anything we collected so far. There is no
+ terminating NUL byte. */
+ free (unprinted);
+
+ return result;
+}
+
+
+static int
+read_block (int fd, const char *fname, off64_t fdlen, off64_t from, off64_t to)
+{
+ assert ((off64_t) min_len_bytes < fdlen);
+
+ if (elfmap == NULL)
+ {
+ /* We need a completely new mapping. */
+ elfmap_off = from & ~(ps - 1);
+ elfmap_base = elfmap = map_file (fd, elfmap_off, fdlen, &elfmap_size);
+
+ if (unlikely (elfmap == MAP_FAILED))
+ /* Let the kernel know we are going to read everything in sequence. */
+ (void) posix_fadvise (fd, 0, 0, POSIX_FADV_SEQUENTIAL);
+ }
+
+ if (unlikely (elfmap == MAP_FAILED))
+ {
+ /* Read from the file descriptor. For this we must position the
+ read pointer. */
+ // XXX Eventually add flag which avoids this if the position
+ // XXX is known to match.
+ if (lseek64 (fd, from, SEEK_SET) != from)
+ error (EXIT_FAILURE, errno, gettext ("lseek64 failed"));
+
+ return read_block_no_mmap (fd, fname, from, to - from);
+ }
+
+ if (to < (off64_t) elfmap_off || from > (off64_t) (elfmap_off + elfmap_size))
+ {
+ /* The existing mapping cannot fit at all. Map the new area.
+ We always map the full range of ELFMAP_SIZE bytes even if
+ this extend beyond the end of the file. The Linux kernel
+ handles this OK if the access pages are not touched. */
+ elfmap_off = from & ~(ps - 1);
+ if (mmap64 (elfmap, elfmap_size, PROT_READ,
+ MAP_PRIVATE | MAP_POPULATE | MAP_FIXED, fd, from)
+ == MAP_FAILED)
+ error (EXIT_FAILURE, errno, gettext ("re-mmap failed"));
+ elfmap_base = elfmap;
+ }
+
+ char *unprinted = NULL;
+
+ /* Use the existing mapping as much as possible. If necessary, map
+ new pages. */
+ if (from >= (off64_t) elfmap_off
+ && from < (off64_t) (elfmap_off + elfmap_size))
+ /* There are at least a few bytes in this mapping which we can
+ use. */
+ process_chunk (fname, elfmap_base + (from - elfmap_off),
+ MIN (to, (off64_t) (elfmap_off + elfmap_size)),
+ MIN (to, (off64_t) (elfmap_off + elfmap_size)) - from,
+ &unprinted);
+
+ if (to > (off64_t) (elfmap_off + elfmap_size))
+ {
+ unsigned char *remap_base = elfmap_base;
+ size_t read_now = elfmap_size - (elfmap_base - elfmap);
+
+ assert (from >= (off64_t) elfmap_off
+ && from < (off64_t) (elfmap_off + elfmap_size));
+ off64_t handled_to = elfmap_off + elfmap_size;
+ assert (elfmap == elfmap_base
+ || (elfmap_base - elfmap
+ == (ptrdiff_t) ((min_len_bytes + ps - 1) & ~(ps - 1))));
+ if (elfmap == elfmap_base)
+ {
+ size_t keep_area = (min_len_bytes + ps - 1) & ~(ps - 1);
+ assert (elfmap_size >= keep_area + ps);
+ /* The keep area is used for the content of the previous
+ buffer we have to keep. This means copying those bytes
+ and for this we have to make the data writable. */
+ if (unlikely (mprotect (elfmap, keep_area, PROT_READ | PROT_WRITE)
+ != 0))
+ error (EXIT_FAILURE, errno, gettext ("mprotect failed"));
+
+ elfmap_base = elfmap + keep_area;
+ }
+
+ while (1)
+ {
+ /* Map the rest of the file, eventually again in pieces.
+ We speed things up with a nice Linux feature. Note
+ that we have at least two pages mapped. */
+ size_t to_keep = unprinted != NULL ? 0 : min_len_bytes;
+
+ assert (read_now >= to_keep);
+ memmove (elfmap_base - to_keep,
+ remap_base + read_now - to_keep, to_keep);
+ remap_base = elfmap_base;
+
+ assert ((elfmap_size - (elfmap_base - elfmap)) % bytes_per_char
+ == 0);
+ read_now = MIN (to - handled_to,
+ (ptrdiff_t) elfmap_size - (elfmap_base - elfmap));
+
+ assert (handled_to % ps == 0);
+ assert (handled_to % bytes_per_char == 0);
+ if (mmap64 (remap_base, read_now, PROT_READ,
+ MAP_PRIVATE | MAP_POPULATE | MAP_FIXED, fd, handled_to)
+ == MAP_FAILED)
+ error (EXIT_FAILURE, errno, gettext ("re=mmap failed"));
+ elfmap_off = handled_to;
+
+ process_chunk (fname, remap_base - to_keep,
+ elfmap_off + (read_now & ~(bytes_per_char - 1)),
+ to_keep + (read_now & ~(bytes_per_char - 1)),
+ &unprinted);
+ handled_to += read_now;
+ if (handled_to >= to)
+ break;
+ }
+ }
+
+ /* Don't print anything we collected so far. There is no
+ terminating NUL byte. */
+ free (unprinted);
+
+ return 0;
+}
+
+
+static int
+read_fd (int fd, const char *fname, off64_t fdlen)
+{
+ return read_block (fd, fname, fdlen, 0, fdlen);
+}
+
+
+static int
+read_elf (Elf *elf, int fd, const char *fname, off64_t fdlen)
+{
+ assert (fdlen >= 0);
+
+ /* We will look at each section separately. The ELF file is not
+ mmapped. The libelf implementation will load the needed parts on
+ demand. Since we only interate over the section header table the
+ memory consumption at this stage is kept minimal. */
+ Elf_Scn *scn = elf_nextscn (elf, NULL);
+ if (scn == NULL)
+ return read_fd (fd, fname, fdlen);
+
+ int result = 0;
+ do
+ {
+ GElf_Shdr shdr_mem;
+ GElf_Shdr *shdr = gelf_getshdr (scn, &shdr_mem);
+
+ /* Only look in sections which are loaded at runtime and
+ actually have content. */
+ if (shdr != NULL && shdr->sh_type != SHT_NOBITS
+ && (shdr->sh_flags & SHF_ALLOC) != 0)
+ result |= read_block (fd, fname, fdlen, shdr->sh_offset,
+ shdr->sh_offset + shdr->sh_size);
+ }
+ while ((scn = elf_nextscn (elf, scn)) != NULL);
+
+ if (elfmap != NULL && elfmap != MAP_FAILED)
+ munmap (elfmap, elfmap_size);
+ elfmap = NULL;
+
+ return result;
+}
projects / platform / upstream / elfutils.git / commitdiff