android_kernel_sony_sdm845/lib/string.c
jianzhou 79bbe9c88c Merge android-4.9.187 (fabc071) into msm-4.9
* refs/heads/tmp-fabc071:
  Linux 4.9.187
  ceph: hold i_ceph_lock when removing caps for freeing inode
  drivers/pps/pps.c: clear offset flags in PPS_SETPARAMS ioctl
  sched/fair: Don't free p->numa_faults with concurrent readers
  Bluetooth: hci_uart: check for missing tty operations
  media: radio-raremono: change devm_k*alloc to k*alloc
  media: cpia2_usb: first wake up, then free in disconnect
  media: au0828: fix null dereference in error path
  ISDN: hfcsusb: checking idx of ep configuration
  arm64: compat: Provide definition for COMPAT_SIGMINSTKSZ
  i2c: qup: fixed releasing dma without flush operation completion
  arm64: dts: marvell: Fix A37xx UART0 register size
  tcp: reset sk_send_head in tcp_write_queue_purge
  ipv6: check sk sk_type and protocol early in ip_mroute_set/getsockopt
  access: avoid the RCU grace period for the temporary subjective credentials
  powerpc/tm: Fix oops on sigreturn on systems without TM
  ALSA: hda - Add a conexant codec entry to let mute led work
  ALSA: line6: Fix wrong altsetting for LINE6_PODHD500_1
  hpet: Fix division by zero in hpet_time_div()
  x86/speculation/mds: Apply more accurate check on hypervisor platform
  x86/sysfb_efi: Add quirks for some devices with swapped width and height
  usb: pci-quirks: Correct AMD PLL quirk detection
  usb: wusbcore: fix unbalanced get/put cluster_id
  locking/lockdep: Hide unused 'class' variable
  locking/lockdep: Fix lock used or unused stats error
  mm/mmu_notifier: use hlist_add_head_rcu()
  9p: pass the correct prototype to read_cache_page
  mm/kmemleak.c: fix check for softirq context
  sh: prevent warnings when using iounmap
  powerpc/eeh: Handle hugepages in ioremap space
  mailbox: handle failed named mailbox channel request
  f2fs: avoid out-of-range memory access
  powerpc/boot: add {get, put}_unaligned_be32 to xz_config.h
  RDMA/rxe: Fill in wc byte_len with IB_WC_RECV_RDMA_WITH_IMM
  perf test mmap-thread-lookup: Initialize variable to suppress memory sanitizer warning
  kallsyms: exclude kasan local symbols on s390
  serial: sh-sci: Fix TX DMA buffer flushing and workqueue races
  serial: sh-sci: Terminate TX DMA during buffer flushing
  RDMA/i40iw: Set queue pair state when being queried
  powerpc/4xx/uic: clear pending interrupt after irq type/pol change
  um: Silence lockdep complaint about mmap_sem
  mfd: hi655x-pmic: Fix missing return value check for devm_regmap_init_mmio_clk
  mfd: arizona: Fix undefined behavior
  mfd: core: Set fwnode for created devices
  recordmcount: Fix spurious mcount entries on powerpc
  iio: iio-utils: Fix possible incorrect mask calculation
  PCI: xilinx-nwl: Fix Multi MSI data programming
  kbuild: Add -Werror=unknown-warning-option to CLANG_FLAGS
  PCI: sysfs: Ignore lockdep for remove attribute
  powerpc/pci/of: Fix OF flags parsing for 64bit BARs
  usb: gadget: Zero ffs_io_data
  tty: serial_core: Set port active bit in uart_port_activate
  drm/rockchip: Properly adjust to a true clock in adjusted_mode
  phy: renesas: rcar-gen2: Fix memory leak at error paths
  drm/virtio: Add memory barriers for capset cache.
  serial: 8250: Fix TX interrupt handling condition
  tty: serial: msm_serial: avoid system lockup condition
  tty/serial: digicolor: Fix digicolor-usart already registered warning
  memstick: Fix error cleanup path of memstick_init
  drm/bridge: sii902x: pixel clock unit is 10kHz instead of 1kHz
  drm/bridge: tc358767: read display_props in get_modes()
  tty: serial: cpm_uart - fix init when SMC is relocated
  pinctrl: rockchip: fix leaked of_node references
  tty: max310x: Fix invalid baudrate divisors calculator
  usb: core: hub: Disable hub-initiated U1/U2
  drm/panel: simple: Fix panel_simple_dsi_probe
  nfsd: Fix overflow causing non-working mounts on 1 TB machines
  nfsd: fix performance-limiting session calculation
  nfsd: give out fewer session slots as limit approaches
  nfsd: increase DRC cache limit
  NFSv4: Fix open create exclusive when the server reboots
  perf/events/amd/uncore: Fix amd_uncore_llc ID to use pre-defined cpu_llc_id
  perf/x86/amd/uncore: Get correct number of cores sharing last level cache
  perf/x86/amd/uncore: Rename 'L2' to 'LLC'
  net: bridge: stp: don't cache eth dest pointer before skb pull
  net: bridge: mcast: fix stale ipv6 hdr pointer when handling v6 query
  net: bridge: mcast: fix stale nsrcs pointer in igmp3/mld2 report handling
  tcp: Reset bytes_acked and bytes_received when disconnecting
  bonding: validate ip header before check IPPROTO_IGMP
  netrom: hold sock when setting skb->destructor
  netrom: fix a memory leak in nr_rx_frame()
  macsec: fix checksumming after decryption
  macsec: fix use-after-free of skb during RX
  vrf: make sure skb->data contains ip header to make routing
  sky2: Disable MSI on ASUS P6T
  rxrpc: Fix send on a connected, but unbound socket
  nfc: fix potential illegal memory access
  net: openvswitch: fix csum updates for MPLS actions
  net: neigh: fix multiple neigh timer scheduling
  net: dsa: mv88e6xxx: wait after reset deactivation
  net: bcmgenet: use promisc for unsupported filters
  ipv4: don't set IPv6 only flags to IPv4 addresses
  igmp: fix memory leak in igmpv3_del_delrec()
  caif-hsi: fix possible deadlock in cfhsi_exit_module()
  bnx2x: Prevent ptp_task to be rescheduled indefinitely
  bnx2x: Prevent load reordering in tx completion processing
  ext4: allow directory holes
  lib/strscpy: Shut up KASAN false-positives in strscpy()
  compiler.h: Add read_word_at_a_time() function.
  compiler.h, kasan: Avoid duplicating __read_once_size_nocheck()
  dm bufio: fix deadlock with loop device
  usb: Handle USB3 remote wakeup for LPM enabled devices correctly
  Bluetooth: Add SMP workaround Microsoft Surface Precision Mouse bug
  intel_th: msu: Fix single mode with disabled IOMMU
  eCryptfs: fix a couple type promotion bugs
  powerpc/watchpoint: Restore NV GPRs while returning from exception
  powerpc/32s: fix suspend/resume when IBATs 4-7 are used
  parisc: Fix kernel panic due invalid values in IAOQ0 or IAOQ1
  parisc: Ensure userspace privilege for ptraced processes in regset functions
  um: Fix FP register size for XSTATE/XSAVE
  um: Allow building and running on older hosts
  crypto: caam - limit output IV to CBC to work around CTR mode DMA issue
  PCI: hv: Fix a use-after-free bug in hv_eject_device_work()
  PCI: hv: Delete the device earlier from hbus->children for hot-remove
  crypto: ccp - Validate the the error value used to index error messages
  gpu: ipu-v3: ipu-ic: Fix saturation bit offset in TPMEM
  coda: pass the host file in vma->vm_file on mmap
  floppy: fix out-of-bounds read in copy_buffer
  floppy: fix invalid pointer dereference in drive_name
  floppy: fix out-of-bounds read in next_valid_format
  floppy: fix div-by-zero in setup_format_params
  take floppy compat ioctls to sodding floppy.c
  libnvdimm/pfn: fix fsdax-mode namespace info-block zero-fields
  Btrfs: add missing inode version, ctime and mtime updates when punching hole
  PCI: Do not poll for PME if the device is in D3cold
  9p/virtio: Add cleanup path in p9_virtio_init
  padata: use smp_mb in padata_reorder to avoid orphaned padata jobs
  drm/nouveau/i2c: Enable i2c pads & busses during preinit
  fs/proc/proc_sysctl.c: fix the default values of i_uid/i_gid on /proc/sys inodes.
  arm64: tegra: Fix AGIC register range
  KVM: x86/vPMU: refine kvm_pmu err msg when event creation failed
  media: coda: Remove unbalanced and unneeded mutex unlock
  media: v4l2: Test type instead of cfg->type in v4l2_ctrl_new_custom()
  ALSA: hda/realtek: apply ALC891 headset fixup to one Dell machine
  ALSA: seq: Break too long mutex context in the write loop
  lib/scatterlist: Fix mapping iterator when sg->offset is greater than PAGE_SIZE
  NFSv4: Handle the special Linux file open access mode
  tracing/snapshot: Resize spare buffer if size changed
  iwlwifi: pcie: don't service an interrupt that was masked
  arm64: tegra: Update Jetson TX1 GPU regulator timings
  regulator: s2mps11: Fix buck7 and buck8 wrong voltages
  Input: gtco - bounds check collection indent level
  crypto: crypto4xx - fix a potential double free in ppc4xx_trng_probe
  crypto: chacha20poly1305 - fix atomic sleep when using async algorithm
  crypto: arm64/sha2-ce - correct digest for empty data in finup
  crypto: arm64/sha1-ce - correct digest for empty data in finup
  crypto: ghash - fix unaligned memory access in ghash_setkey()
  scsi: mac_scsi: Increase PIO/PDMA transfer length threshold
  scsi: NCR5380: Always re-enable reselection interrupt
  scsi: NCR5380: Reduce goto statements in NCR5380_select()
  xen: let alloc_xenballooned_pages() fail if not enough memory free
  gtp: fix use-after-free in gtp_newlink()
  gtp: fix Illegal context switch in RCU read-side critical section.
  Bluetooth: validate BLE connection interval updates
  Bluetooth: Check state in l2cap_disconnect_rsp
  Bluetooth: 6lowpan: search for destination address in all peers
  Bluetooth: hci_bcsp: Fix memory leak in rx_skb
  gpiolib: Fix references to gpiod_[gs]et_*value_cansleep() variants
  net: usb: asix: init MAC address buffers
  iwlwifi: mvm: Drop large non sta frames
  bcache: check c->gc_thread by IS_ERR_OR_NULL in cache_set_flush()
  EDAC: Fix global-out-of-bounds write when setting edac_mc_poll_msec
  crypto: asymmetric_keys - select CRYPTO_HASH where needed
  ixgbe: Check DDM existence in transceiver before access
  rslib: Fix handling of of caller provided syndrome
  rslib: Fix decoding of shortened codes
  clocksource/drivers/exynos_mct: Increase priority over ARM arch timer
  libata: don't request sense data on !ZAC ATA devices
  perf tools: Increase MAX_NR_CPUS and MAX_CACHES
  ath10k: fix PCIE device wake up failed
  mt7601u: fix possible memory leak when the device is disconnected
  x86/build: Add 'set -e' to mkcapflags.sh to delete broken capflags.c
  mt7601u: do not schedule rx_tasklet when the device has been disconnected
  media: coda: increment sequence offset for the last returned frame
  media: coda: fix mpeg2 sequence number handling
  acpi/arm64: ignore 5.1 FADTs that are reported as 5.0
  timer_list: Guard procfs specific code
  ntp: Limit TAI-UTC offset
  media: i2c: fix warning same module names
  ipsec: select crypto ciphers for xfrm_algo
  EDAC/sysfs: Fix memory leak when creating a csrow object
  ipoib: correcly show a VF hardware address
  vhost_net: disable zerocopy by default
  perf evsel: Make perf_evsel__name() accept a NULL argument
  xfrm: fix sa selector validation
  blkcg, writeback: dead memcgs shouldn't contribute to writeback ownership arbitration
  rcu: Force inlining of rcu_read_lock()
  bpf: silence warning messages in core
  regmap: fix bulk writes on paged registers
  gpio: omap: ensure irq is enabled before wakeup
  gpio: omap: fix lack of irqstatus_raw0 for OMAP4
  perf test 6: Fix missing kvm module load for s390
  perf cs-etm: Properly set the value of 'old' and 'head' in snapshot mode
  s390/qdio: handle PENDING state for QEBSM devices
  net: axienet: Fix race condition causing TX hang
  net: fec: Do not use netdev messages too early
  cpupower : frequency-set -r option misses the last cpu in related cpu list
  media: wl128x: Fix some error handling in fm_v4l2_init_video_device()
  locking/lockdep: Fix merging of hlocks with non-zero references
  tua6100: Avoid build warnings.
  crypto: talitos - Align SEC1 accesses to 32 bits boundaries.
  crypto: talitos - properly handle split ICV.
  net: phy: Check against net_device being NULL
  media: staging: media: davinci_vpfe: - Fix for memory leak if decoder initialization fails.
  media: mc-device.c: don't memset __user pointer contents
  xfrm: Fix xfrm sel prefix length validation
  af_key: fix leaks in key_pol_get_resp and dump_sp.
  signal/pid_namespace: Fix reboot_pid_ns to use send_sig not force_sig
  net: stmmac: dwmac4/5: Clear unused address entries
  net: stmmac: dwmac1000: Clear unused address entries
  media: media_device_enum_links32: clean a reserved field
  media: vpss: fix a potential NULL pointer dereference
  media: marvell-ccic: fix DMA s/g desc number calculation
  crypto: talitos - fix skcipher failure due to wrong output IV
  media: dvb: usb: fix use after free in dvb_usb_device_exit
  batman-adv: fix for leaked TVLV handler.
  ath: DFS JP domain W56 fixed pulse type 3 RADAR detection
  ath6kl: add some bounds checking
  ath9k: Check for errors when reading SREV register
  ath10k: Do not send probe response template for mesh
  dmaengine: imx-sdma: fix use-after-free on probe error path
  arm64/efi: Mark __efistub_stext_offset as an absolute symbol explicitly
  MIPS: fix build on non-linux hosts
  MIPS: ath79: fix ar933x uart parity mode
  ext4: remove unused value
  f2fs: use EINVAL for superblock with invalid magic
  f2fs: fix to read source block before invalidating it
  f2fs: remove redundant check from f2fs_setflags_common()
  f2fs: use generic checking and prep function for FS_IOC_SETFLAGS
  vfs: use READ_ONCE() to access ->i_link
  fs, fscrypt: clear DCACHE_ENCRYPTED_NAME when unaliasing directory
  ANDROID: enable CONFIG_RTC_DRV_TEST on cuttlefish
  ANDROID: xfrm: remove in_compat_syscall() checks
  UPSTREAM: binder: Set end of SG buffer area properly.
  fscrypt: cache decrypted symlink target in ->i_link
  fscrypt: fix race where ->lookup() marks plaintext dentry as ciphertext
  ext4: remove unused d_name argument from ext4_search_dir() et al.
  fscrypt: only set dentry_operations on ciphertext dentries
  fscrypt: fix race allowing rename() and link() of ciphertext dentries
  fscrypt: clean up and improve dentry revalidation
  fscrypt: use READ_ONCE() to access ->i_crypt_info
  fscrypt: remove WARN_ON_ONCE() when decryption fails
  fscrypt: drop inode argument from fscrypt_get_ctx()
  f2fs: improve print log in f2fs_sanity_check_ckpt()
  f2fs: avoid out-of-range memory access
  f2fs: fix to avoid long latency during umount
  f2fs: allow all the users to pin a file
  f2fs: support swap file w/ DIO
  f2fs: allocate blocks for pinned file
  f2fs: fix is_idle() check for discard type
  f2fs: add a rw_sem to cover quota flag changes
  f2fs: set SBI_NEED_FSCK for xattr corruption case
  f2fs: use generic EFSBADCRC/EFSCORRUPTED
  f2fs: Use DIV_ROUND_UP() instead of open-coding
  f2fs: print kernel message if filesystem is inconsistent
  f2fs: introduce f2fs_<level> macros to wrap f2fs_printk()
  f2fs: avoid get_valid_blocks() for cleanup
  f2fs: ioctl for removing a range from F2FS
  f2fs: only set project inherit bit for directory
  f2fs: separate f2fs i_flags from fs_flags and ext4 i_flags
  f2fs: Add option to limit required GC for checkpoint=disable
  f2fs: Fix accounting for unusable blocks
  f2fs: Fix root reserved on remount
  f2fs: Lower threshold for disable_cp_again
  f2fs: fix sparse warning
  f2fs: fix f2fs_show_options to show nodiscard mount option
  f2fs: add error prints for debugging mount failure
  f2fs: fix to do sanity check on segment bitmap of LFS curseg
  f2fs: add missing sysfs entries in documentation
  f2fs: fix to avoid deadloop if data_flush is on
  f2fs: always assume that the device is idle under gc_urgent
  f2fs: add bio cache for IPU
  f2fs: allow ssr block allocation during checkpoint=disable period
  f2fs: fix to check layout on last valid checkpoint park

Conflicts:
	drivers/tty/serial/msm_serial.c
	fs/crypto/bio.c
	fs/crypto/keyinfo.c
	fs/f2fs/data.c

Change-Id: I400b66ca62d751839b3e0499cb6c797f5f70b554
Signed-off-by: jianzhou <jianzhou@codeaurora.org>
2019-10-11 14:38:02 +08:00

981 lines
21 KiB
C

/*
* linux/lib/string.c
*
* Copyright (C) 1991, 1992 Linus Torvalds
*/
/*
* stupid library routines.. The optimized versions should generally be found
* as inline code in <asm-xx/string.h>
*
* These are buggy as well..
*
* * Fri Jun 25 1999, Ingo Oeser <ioe@informatik.tu-chemnitz.de>
* - Added strsep() which will replace strtok() soon (because strsep() is
* reentrant and should be faster). Use only strsep() in new code, please.
*
* * Sat Feb 09 2002, Jason Thomas <jason@topic.com.au>,
* Matthew Hawkins <matt@mh.dropbear.id.au>
* - Kissed strtok() goodbye
*/
#include <linux/types.h>
#include <linux/string.h>
#include <linux/ctype.h>
#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/bug.h>
#include <linux/errno.h>
#include <asm/byteorder.h>
#include <asm/word-at-a-time.h>
#include <asm/page.h>
#ifndef __HAVE_ARCH_STRNCASECMP
/**
* strncasecmp - Case insensitive, length-limited string comparison
* @s1: One string
* @s2: The other string
* @len: the maximum number of characters to compare
*/
int strncasecmp(const char *s1, const char *s2, size_t len)
{
/* Yes, Virginia, it had better be unsigned */
unsigned char c1, c2;
if (!len)
return 0;
do {
c1 = *s1++;
c2 = *s2++;
if (!c1 || !c2)
break;
if (c1 == c2)
continue;
c1 = tolower(c1);
c2 = tolower(c2);
if (c1 != c2)
break;
} while (--len);
return (int)c1 - (int)c2;
}
EXPORT_SYMBOL(strncasecmp);
#endif
#ifndef __HAVE_ARCH_STRCASECMP
int strcasecmp(const char *s1, const char *s2)
{
int c1, c2;
do {
c1 = tolower(*s1++);
c2 = tolower(*s2++);
} while (c1 == c2 && c1 != 0);
return c1 - c2;
}
EXPORT_SYMBOL(strcasecmp);
#endif
#ifndef __HAVE_ARCH_STRCPY
/**
* strcpy - Copy a %NUL terminated string
* @dest: Where to copy the string to
* @src: Where to copy the string from
*/
#undef strcpy
char *strcpy(char *dest, const char *src)
{
char *tmp = dest;
while ((*dest++ = *src++) != '\0')
/* nothing */;
return tmp;
}
EXPORT_SYMBOL(strcpy);
#endif
#ifndef __HAVE_ARCH_STRNCPY
/**
* strncpy - Copy a length-limited, C-string
* @dest: Where to copy the string to
* @src: Where to copy the string from
* @count: The maximum number of bytes to copy
*
* The result is not %NUL-terminated if the source exceeds
* @count bytes.
*
* In the case where the length of @src is less than that of
* count, the remainder of @dest will be padded with %NUL.
*
*/
char *strncpy(char *dest, const char *src, size_t count)
{
char *tmp = dest;
while (count) {
if ((*tmp = *src) != 0)
src++;
tmp++;
count--;
}
return dest;
}
EXPORT_SYMBOL(strncpy);
#endif
#ifndef __HAVE_ARCH_STRLCPY
/**
* strlcpy - Copy a C-string into a sized buffer
* @dest: Where to copy the string to
* @src: Where to copy the string from
* @size: size of destination buffer
*
* Compatible with *BSD: the result is always a valid
* NUL-terminated string that fits in the buffer (unless,
* of course, the buffer size is zero). It does not pad
* out the result like strncpy() does.
*/
size_t strlcpy(char *dest, const char *src, size_t size)
{
size_t ret = strlen(src);
if (size) {
size_t len = (ret >= size) ? size - 1 : ret;
memcpy(dest, src, len);
dest[len] = '\0';
}
return ret;
}
EXPORT_SYMBOL(strlcpy);
#endif
#ifndef __HAVE_ARCH_STRSCPY
/**
* strscpy - Copy a C-string into a sized buffer
* @dest: Where to copy the string to
* @src: Where to copy the string from
* @count: Size of destination buffer
*
* Copy the string, or as much of it as fits, into the dest buffer.
* The routine returns the number of characters copied (not including
* the trailing NUL) or -E2BIG if the destination buffer wasn't big enough.
* The behavior is undefined if the string buffers overlap.
* The destination buffer is always NUL terminated, unless it's zero-sized.
*
* Preferred to strlcpy() since the API doesn't require reading memory
* from the src string beyond the specified "count" bytes, and since
* the return value is easier to error-check than strlcpy()'s.
* In addition, the implementation is robust to the string changing out
* from underneath it, unlike the current strlcpy() implementation.
*
* Preferred to strncpy() since it always returns a valid string, and
* doesn't unnecessarily force the tail of the destination buffer to be
* zeroed. If the zeroing is desired, it's likely cleaner to use strscpy()
* with an overflow test, then just memset() the tail of the dest buffer.
*/
ssize_t strscpy(char *dest, const char *src, size_t count)
{
const struct word_at_a_time constants = WORD_AT_A_TIME_CONSTANTS;
size_t max = count;
long res = 0;
if (count == 0)
return -E2BIG;
#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
/*
* If src is unaligned, don't cross a page boundary,
* since we don't know if the next page is mapped.
*/
if ((long)src & (sizeof(long) - 1)) {
size_t limit = PAGE_SIZE - ((long)src & (PAGE_SIZE - 1));
if (limit < max)
max = limit;
}
#else
/* If src or dest is unaligned, don't do word-at-a-time. */
if (((long) dest | (long) src) & (sizeof(long) - 1))
max = 0;
#endif
while (max >= sizeof(unsigned long)) {
unsigned long c, data;
c = read_word_at_a_time(src+res);
if (has_zero(c, &data, &constants)) {
data = prep_zero_mask(c, data, &constants);
data = create_zero_mask(data);
*(unsigned long *)(dest+res) = c & zero_bytemask(data);
return res + find_zero(data);
}
*(unsigned long *)(dest+res) = c;
res += sizeof(unsigned long);
count -= sizeof(unsigned long);
max -= sizeof(unsigned long);
}
while (count) {
char c;
c = src[res];
dest[res] = c;
if (!c)
return res;
res++;
count--;
}
/* Hit buffer length without finding a NUL; force NUL-termination. */
if (res)
dest[res-1] = '\0';
return -E2BIG;
}
EXPORT_SYMBOL(strscpy);
#endif
#ifndef __HAVE_ARCH_STRCAT
/**
* strcat - Append one %NUL-terminated string to another
* @dest: The string to be appended to
* @src: The string to append to it
*/
#undef strcat
char *strcat(char *dest, const char *src)
{
char *tmp = dest;
while (*dest)
dest++;
while ((*dest++ = *src++) != '\0')
;
return tmp;
}
EXPORT_SYMBOL(strcat);
#endif
#ifndef __HAVE_ARCH_STRNCAT
/**
* strncat - Append a length-limited, C-string to another
* @dest: The string to be appended to
* @src: The string to append to it
* @count: The maximum numbers of bytes to copy
*
* Note that in contrast to strncpy(), strncat() ensures the result is
* terminated.
*/
char *strncat(char *dest, const char *src, size_t count)
{
char *tmp = dest;
if (count) {
while (*dest)
dest++;
while ((*dest++ = *src++) != 0) {
if (--count == 0) {
*dest = '\0';
break;
}
}
}
return tmp;
}
EXPORT_SYMBOL(strncat);
#endif
#ifndef __HAVE_ARCH_STRLCAT
/**
* strlcat - Append a length-limited, C-string to another
* @dest: The string to be appended to
* @src: The string to append to it
* @count: The size of the destination buffer.
*/
size_t strlcat(char *dest, const char *src, size_t count)
{
size_t dsize = strlen(dest);
size_t len = strlen(src);
size_t res = dsize + len;
/* This would be a bug */
BUG_ON(dsize >= count);
dest += dsize;
count -= dsize;
if (len >= count)
len = count-1;
memcpy(dest, src, len);
dest[len] = 0;
return res;
}
EXPORT_SYMBOL(strlcat);
#endif
#ifndef __HAVE_ARCH_STRCMP
/**
* strcmp - Compare two strings
* @cs: One string
* @ct: Another string
*/
#undef strcmp
int strcmp(const char *cs, const char *ct)
{
unsigned char c1, c2;
while (1) {
c1 = *cs++;
c2 = *ct++;
if (c1 != c2)
return c1 < c2 ? -1 : 1;
if (!c1)
break;
}
return 0;
}
EXPORT_SYMBOL(strcmp);
#endif
#ifndef __HAVE_ARCH_STRNCMP
/**
* strncmp - Compare two length-limited strings
* @cs: One string
* @ct: Another string
* @count: The maximum number of bytes to compare
*/
int strncmp(const char *cs, const char *ct, size_t count)
{
unsigned char c1, c2;
while (count) {
c1 = *cs++;
c2 = *ct++;
if (c1 != c2)
return c1 < c2 ? -1 : 1;
if (!c1)
break;
count--;
}
return 0;
}
EXPORT_SYMBOL(strncmp);
#endif
#ifndef __HAVE_ARCH_STRCHR
/**
* strchr - Find the first occurrence of a character in a string
* @s: The string to be searched
* @c: The character to search for
*/
char *strchr(const char *s, int c)
{
for (; *s != (char)c; ++s)
if (*s == '\0')
return NULL;
return (char *)s;
}
EXPORT_SYMBOL(strchr);
#endif
#ifndef __HAVE_ARCH_STRCHRNUL
/**
* strchrnul - Find and return a character in a string, or end of string
* @s: The string to be searched
* @c: The character to search for
*
* Returns pointer to first occurrence of 'c' in s. If c is not found, then
* return a pointer to the null byte at the end of s.
*/
char *strchrnul(const char *s, int c)
{
while (*s && *s != (char)c)
s++;
return (char *)s;
}
EXPORT_SYMBOL(strchrnul);
#endif
#ifndef __HAVE_ARCH_STRRCHR
/**
* strrchr - Find the last occurrence of a character in a string
* @s: The string to be searched
* @c: The character to search for
*/
char *strrchr(const char *s, int c)
{
const char *last = NULL;
do {
if (*s == (char)c)
last = s;
} while (*s++);
return (char *)last;
}
EXPORT_SYMBOL(strrchr);
#endif
#ifndef __HAVE_ARCH_STRNCHR
/**
* strnchr - Find a character in a length limited string
* @s: The string to be searched
* @count: The number of characters to be searched
* @c: The character to search for
*/
char *strnchr(const char *s, size_t count, int c)
{
for (; count-- && *s != '\0'; ++s)
if (*s == (char)c)
return (char *)s;
return NULL;
}
EXPORT_SYMBOL(strnchr);
#endif
/**
* skip_spaces - Removes leading whitespace from @str.
* @str: The string to be stripped.
*
* Returns a pointer to the first non-whitespace character in @str.
*/
char *skip_spaces(const char *str)
{
while (isspace(*str))
++str;
return (char *)str;
}
EXPORT_SYMBOL(skip_spaces);
/**
* strim - Removes leading and trailing whitespace from @s.
* @s: The string to be stripped.
*
* Note that the first trailing whitespace is replaced with a %NUL-terminator
* in the given string @s. Returns a pointer to the first non-whitespace
* character in @s.
*/
char *strim(char *s)
{
size_t size;
char *end;
size = strlen(s);
if (!size)
return s;
end = s + size - 1;
while (end >= s && isspace(*end))
end--;
*(end + 1) = '\0';
return skip_spaces(s);
}
EXPORT_SYMBOL(strim);
#ifndef __HAVE_ARCH_STRLEN
/**
* strlen - Find the length of a string
* @s: The string to be sized
*/
size_t strlen(const char *s)
{
const char *sc;
for (sc = s; *sc != '\0'; ++sc)
/* nothing */;
return sc - s;
}
EXPORT_SYMBOL(strlen);
#endif
#ifndef __HAVE_ARCH_STRNLEN
/**
* strnlen - Find the length of a length-limited string
* @s: The string to be sized
* @count: The maximum number of bytes to search
*/
size_t strnlen(const char *s, size_t count)
{
const char *sc;
for (sc = s; count-- && *sc != '\0'; ++sc)
/* nothing */;
return sc - s;
}
EXPORT_SYMBOL(strnlen);
#endif
#ifndef __HAVE_ARCH_STRSPN
/**
* strspn - Calculate the length of the initial substring of @s which only contain letters in @accept
* @s: The string to be searched
* @accept: The string to search for
*/
size_t strspn(const char *s, const char *accept)
{
const char *p;
const char *a;
size_t count = 0;
for (p = s; *p != '\0'; ++p) {
for (a = accept; *a != '\0'; ++a) {
if (*p == *a)
break;
}
if (*a == '\0')
return count;
++count;
}
return count;
}
EXPORT_SYMBOL(strspn);
#endif
#ifndef __HAVE_ARCH_STRCSPN
/**
* strcspn - Calculate the length of the initial substring of @s which does not contain letters in @reject
* @s: The string to be searched
* @reject: The string to avoid
*/
size_t strcspn(const char *s, const char *reject)
{
const char *p;
const char *r;
size_t count = 0;
for (p = s; *p != '\0'; ++p) {
for (r = reject; *r != '\0'; ++r) {
if (*p == *r)
return count;
}
++count;
}
return count;
}
EXPORT_SYMBOL(strcspn);
#endif
#ifndef __HAVE_ARCH_STRPBRK
/**
* strpbrk - Find the first occurrence of a set of characters
* @cs: The string to be searched
* @ct: The characters to search for
*/
char *strpbrk(const char *cs, const char *ct)
{
const char *sc1, *sc2;
for (sc1 = cs; *sc1 != '\0'; ++sc1) {
for (sc2 = ct; *sc2 != '\0'; ++sc2) {
if (*sc1 == *sc2)
return (char *)sc1;
}
}
return NULL;
}
EXPORT_SYMBOL(strpbrk);
#endif
#ifndef __HAVE_ARCH_STRSEP
/**
* strsep - Split a string into tokens
* @s: The string to be searched
* @ct: The characters to search for
*
* strsep() updates @s to point after the token, ready for the next call.
*
* It returns empty tokens, too, behaving exactly like the libc function
* of that name. In fact, it was stolen from glibc2 and de-fancy-fied.
* Same semantics, slimmer shape. ;)
*/
char *strsep(char **s, const char *ct)
{
char *sbegin = *s;
char *end;
if (sbegin == NULL)
return NULL;
end = strpbrk(sbegin, ct);
if (end)
*end++ = '\0';
*s = end;
return sbegin;
}
EXPORT_SYMBOL(strsep);
#endif
/**
* sysfs_streq - return true if strings are equal, modulo trailing newline
* @s1: one string
* @s2: another string
*
* This routine returns true iff two strings are equal, treating both
* NUL and newline-then-NUL as equivalent string terminations. It's
* geared for use with sysfs input strings, which generally terminate
* with newlines but are compared against values without newlines.
*/
bool sysfs_streq(const char *s1, const char *s2)
{
while (*s1 && *s1 == *s2) {
s1++;
s2++;
}
if (*s1 == *s2)
return true;
if (!*s1 && *s2 == '\n' && !s2[1])
return true;
if (*s1 == '\n' && !s1[1] && !*s2)
return true;
return false;
}
EXPORT_SYMBOL(sysfs_streq);
/**
* match_string - matches given string in an array
* @array: array of strings
* @n: number of strings in the array or -1 for NULL terminated arrays
* @string: string to match with
*
* Return:
* index of a @string in the @array if matches, or %-EINVAL otherwise.
*/
int match_string(const char * const *array, size_t n, const char *string)
{
int index;
const char *item;
for (index = 0; index < n; index++) {
item = array[index];
if (!item)
break;
if (!strcmp(item, string))
return index;
}
return -EINVAL;
}
EXPORT_SYMBOL(match_string);
#ifndef __HAVE_ARCH_MEMSET
/**
* memset - Fill a region of memory with the given value
* @s: Pointer to the start of the area.
* @c: The byte to fill the area with
* @count: The size of the area.
*
* Do not use memset() to access IO space, use memset_io() instead.
*/
void *memset(void *s, int c, size_t count)
{
char *xs = s;
while (count--)
*xs++ = c;
return s;
}
EXPORT_SYMBOL(memset);
#endif
/**
* memzero_explicit - Fill a region of memory (e.g. sensitive
* keying data) with 0s.
* @s: Pointer to the start of the area.
* @count: The size of the area.
*
* Note: usually using memset() is just fine (!), but in cases
* where clearing out _local_ data at the end of a scope is
* necessary, memzero_explicit() should be used instead in
* order to prevent the compiler from optimising away zeroing.
*
* memzero_explicit() doesn't need an arch-specific version as
* it just invokes the one of memset() implicitly.
*/
void memzero_explicit(void *s, size_t count)
{
memset(s, 0, count);
barrier_data(s);
}
EXPORT_SYMBOL(memzero_explicit);
#ifndef __HAVE_ARCH_MEMCPY
/**
* memcpy - Copy one area of memory to another
* @dest: Where to copy to
* @src: Where to copy from
* @count: The size of the area.
*
* You should not use this function to access IO space, use memcpy_toio()
* or memcpy_fromio() instead.
*/
void *memcpy(void *dest, const void *src, size_t count)
{
char *tmp = dest;
const char *s = src;
while (count--)
*tmp++ = *s++;
return dest;
}
EXPORT_SYMBOL(memcpy);
#endif
#ifndef __HAVE_ARCH_MEMMOVE
/**
* memmove - Copy one area of memory to another
* @dest: Where to copy to
* @src: Where to copy from
* @count: The size of the area.
*
* Unlike memcpy(), memmove() copes with overlapping areas.
*/
void *memmove(void *dest, const void *src, size_t count)
{
char *tmp;
const char *s;
if (dest <= src) {
tmp = dest;
s = src;
while (count--)
*tmp++ = *s++;
} else {
tmp = dest;
tmp += count;
s = src;
s += count;
while (count--)
*--tmp = *--s;
}
return dest;
}
EXPORT_SYMBOL(memmove);
#endif
#ifndef __HAVE_ARCH_MEMCMP
/**
* memcmp - Compare two areas of memory
* @cs: One area of memory
* @ct: Another area of memory
* @count: The size of the area.
*/
#undef memcmp
__visible int memcmp(const void *cs, const void *ct, size_t count)
{
const unsigned char *su1, *su2;
int res = 0;
for (su1 = cs, su2 = ct; 0 < count; ++su1, ++su2, count--)
if ((res = *su1 - *su2) != 0)
break;
return res;
}
EXPORT_SYMBOL(memcmp);
#endif
#ifndef __HAVE_ARCH_BCMP
/**
* bcmp - returns 0 if and only if the buffers have identical contents.
* @a: pointer to first buffer.
* @b: pointer to second buffer.
* @len: size of buffers.
*
* The sign or magnitude of a non-zero return value has no particular
* meaning, and architectures may implement their own more efficient bcmp(). So
* while this particular implementation is a simple (tail) call to memcmp, do
* not rely on anything but whether the return value is zero or non-zero.
*/
#undef bcmp
int bcmp(const void *a, const void *b, size_t len)
{
return memcmp(a, b, len);
}
EXPORT_SYMBOL(bcmp);
#endif
#ifndef __HAVE_ARCH_MEMSCAN
/**
* memscan - Find a character in an area of memory.
* @addr: The memory area
* @c: The byte to search for
* @size: The size of the area.
*
* returns the address of the first occurrence of @c, or 1 byte past
* the area if @c is not found
*/
void *memscan(void *addr, int c, size_t size)
{
unsigned char *p = addr;
while (size) {
if (*p == c)
return (void *)p;
p++;
size--;
}
return (void *)p;
}
EXPORT_SYMBOL(memscan);
#endif
#ifndef __HAVE_ARCH_STRSTR
/**
* strstr - Find the first substring in a %NUL terminated string
* @s1: The string to be searched
* @s2: The string to search for
*/
char *strstr(const char *s1, const char *s2)
{
size_t l1, l2;
l2 = strlen(s2);
if (!l2)
return (char *)s1;
l1 = strlen(s1);
while (l1 >= l2) {
l1--;
if (!memcmp(s1, s2, l2))
return (char *)s1;
s1++;
}
return NULL;
}
EXPORT_SYMBOL(strstr);
#endif
#ifndef __HAVE_ARCH_STRNSTR
/**
* strnstr - Find the first substring in a length-limited string
* @s1: The string to be searched
* @s2: The string to search for
* @len: the maximum number of characters to search
*/
char *strnstr(const char *s1, const char *s2, size_t len)
{
size_t l2;
l2 = strlen(s2);
if (!l2)
return (char *)s1;
while (len >= l2) {
len--;
if (!memcmp(s1, s2, l2))
return (char *)s1;
s1++;
}
return NULL;
}
EXPORT_SYMBOL(strnstr);
#endif
#ifndef __HAVE_ARCH_MEMCHR
/**
* memchr - Find a character in an area of memory.
* @s: The memory area
* @c: The byte to search for
* @n: The size of the area.
*
* returns the address of the first occurrence of @c, or %NULL
* if @c is not found
*/
void *memchr(const void *s, int c, size_t n)
{
const unsigned char *p = s;
while (n-- != 0) {
if ((unsigned char)c == *p++) {
return (void *)(p - 1);
}
}
return NULL;
}
EXPORT_SYMBOL(memchr);
#endif
static void *check_bytes8(const u8 *start, u8 value, unsigned int bytes)
{
while (bytes) {
if (*start != value)
return (void *)start;
start++;
bytes--;
}
return NULL;
}
/**
* memchr_inv - Find an unmatching character in an area of memory.
* @start: The memory area
* @c: Find a character other than c
* @bytes: The size of the area.
*
* returns the address of the first character other than @c, or %NULL
* if the whole buffer contains just @c.
*/
void *memchr_inv(const void *start, int c, size_t bytes)
{
u8 value = c;
u64 value64;
unsigned int words, prefix;
if (bytes <= 16)
return check_bytes8(start, value, bytes);
value64 = value;
#if defined(CONFIG_ARCH_HAS_FAST_MULTIPLIER) && BITS_PER_LONG == 64
value64 *= 0x0101010101010101ULL;
#elif defined(CONFIG_ARCH_HAS_FAST_MULTIPLIER)
value64 *= 0x01010101;
value64 |= value64 << 32;
#else
value64 |= value64 << 8;
value64 |= value64 << 16;
value64 |= value64 << 32;
#endif
prefix = (unsigned long)start % 8;
if (prefix) {
u8 *r;
prefix = 8 - prefix;
r = check_bytes8(start, value, prefix);
if (r)
return r;
start += prefix;
bytes -= prefix;
}
words = bytes / 8;
while (words) {
if (*(u64 *)start != value64)
return check_bytes8(start, value, 8);
start += 8;
words--;
}
return check_bytes8(start, value, bytes % 8);
}
EXPORT_SYMBOL(memchr_inv);
/**
* strreplace - Replace all occurrences of character in string.
* @s: The string to operate on.
* @old: The character being replaced.
* @new: The character @old is replaced with.
*
* Returns pointer to the nul byte at the end of @s.
*/
char *strreplace(char *s, char old, char new)
{
for (; *s; ++s)
if (*s == old)
*s = new;
return s;
}
EXPORT_SYMBOL(strreplace);
void fortify_panic(const char *name)
{
pr_emerg("detected buffer overflow in %s\n", name);
BUG();
}
EXPORT_SYMBOL(fortify_panic);