Message ID | 1434354995-9839-2-git-send-email-hw.claudio@gmail.com |
---|---|
State | New |
Headers | show |
hw.claudio@gmail.com writes: > From: Claudio Fontana <claudio.fontana@huawei.com> > > if the memmem function is missing, provide a trivial replacement. > > Signed-off-by: Claudio Fontana <claudio.fontana@huawei.com> > Reviewed-by: Eric Blake <eblake@redhat.com> > Acked-by: Luiz Capitulino <lcapitulino@redhat.com> > --- > configure | 15 +++++++++++++ > include/qemu/osdep.h | 4 ++++ > util/Makefile.objs | 1 + > util/memmem.c | 63 ++++++++++++++++++++++++++++++++++++++++++++++++++++ > 4 files changed, 83 insertions(+) > create mode 100644 util/memmem.c > > diff --git a/configure b/configure > index 409edf9..9e04269 100755 > --- a/configure > +++ b/configure > @@ -3091,6 +3091,17 @@ if compile_prog "" "" ; then > fi > > ########################################## > +# memmem probe > +cat > $TMPC <<EOF > +#include <string.h> > +int main(int argc, char *argv[]) { return memmem(argv[0], 0, argv[0], 0) != argv[0]; } > +EOF > +memmem=no > +if compile_prog "" "" ; then > + memmem=yes > +fi > + > +########################################## > # fdt probe > # fdt support is mandatory for at least some target architectures, > # so insist on it if we're building those system emulators. > @@ -4473,6 +4484,7 @@ echo "RDMA support $rdma" > echo "TCG interpreter $tcg_interpreter" > echo "fdt support $fdt" > echo "preadv support $preadv" > +echo "memmem support $memmem" > echo "fdatasync $fdatasync" > echo "madvise $madvise" > echo "posix_madvise $posix_madvise" > @@ -4822,6 +4834,9 @@ fi > if test "$preadv" = "yes" ; then > echo "CONFIG_PREADV=y" >> $config_host_mak > fi > +if test "$memmem" = "yes" ; then > + echo "CONFIG_MEMMEM=y" >> $config_host_mak > +fi > if test "$fdt" = "yes" ; then > echo "CONFIG_FDT=y" >> $config_host_mak > fi > diff --git a/include/qemu/osdep.h b/include/qemu/osdep.h > index 3247364..abc5486 100644 > --- a/include/qemu/osdep.h > +++ b/include/qemu/osdep.h > @@ -201,6 +201,10 @@ ssize_t writev(int fd, const struct iovec *iov, int iov_cnt); > #include <sys/uio.h> > #endif > > +#ifndef CONFIG_MEMMEM > +void *memmem(const void *hay, size_t hay_len, const void *s, size_t s_len); > +#endif /* !CONFIG_MEMMEM */ > + > #ifdef _WIN32 > static inline void qemu_timersub(const struct timeval *val1, > const struct timeval *val2, > diff --git a/util/Makefile.objs b/util/Makefile.objs > index ceaba30..628242f 100644 > --- a/util/Makefile.objs > +++ b/util/Makefile.objs > @@ -1,6 +1,7 @@ > util-obj-y = osdep.o cutils.o unicode.o qemu-timer-common.o > util-obj-$(CONFIG_WIN32) += oslib-win32.o qemu-thread-win32.o event_notifier-win32.o > util-obj-$(CONFIG_POSIX) += oslib-posix.o qemu-thread-posix.o event_notifier-posix.o qemu-openpty.o > +util-obj-$(call lnot,$(CONFIG_MEMMEM)) += memmem.o > util-obj-y += envlist.o path.o module.o > util-obj-$(call lnot,$(CONFIG_INT128)) += host-utils.o > util-obj-y += bitmap.o bitops.o hbitmap.o > diff --git a/util/memmem.c b/util/memmem.c > new file mode 100644 > index 0000000..16ac611 > --- /dev/null > +++ b/util/memmem.c > @@ -0,0 +1,63 @@ > +/* > + * memmem replacement function > + * > + * Copyright (C) 2015 Huawei Technologies Duesseldorf GmbH > + * Written by Claudio Fontana <claudio.fontana@huawei.com> > + * > + * Permission is hereby granted, free of charge, to any person obtaining a copy > + * of this software and associated documentation files (the "Software"), to deal > + * in the Software without restriction, including without limitation the rights > + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell > + * copies of the Software, and to permit persons to whom the Software is > + * furnished to do so, subject to the following conditions: > + * > + * The above copyright notice and this permission notice shall be included in > + * all copies or substantial portions of the Software. > + * > + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR > + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, > + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL > + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER > + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, > + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN > + * THE SOFTWARE. > + */ > + > +#include <qemu-common.h> #include "qemu-common.h", please, like everywhere else. > + > +/* > + * Search for the first occurrence of a binary string ("needle") > + * in a memory region ("haystack"). > + * > + * If needle length is 0, it returns the pointer to the haystack. > + * Otherwise it returns the pointer to the first character of the first > + * occurrence of the needle in the haystack, or NULL if none are found. > + * > + */ > +void * > +memmem(const void *haystack, size_t hay_len, const void *needle, size_t s_len) I prefer function comments to follow a strict pattern: /* * Headline explaining the function's purpose[*] * Zero or more paragraphs explaining preconditions, side effects, * return values, error conditions. */ [*] If you can't come up with a headline fitting into a single line, chances are the function does too many things. Calling the size of @needle @s_len is odd. What about: /* * Return the first occurrence of @needle in @haystack, or else NULL. * @needle consists of @needle_sz bytes. * @haystack consists of @haystack_sz bytes. * Note: returns @haystack when @needle_sz is zero, because an empty * needle matches anywhere. */ void * memmem(const void *haystack, size_t haystack_sz, const void *needle, size_t needle_sz) > +{ > + const unsigned char *hay = (const unsigned char *)haystack; > + const unsigned char *s = (const unsigned char *)needle; Superfluous casts. > + const unsigned char *last = hay + (hay_len - s_len); > + > + if (s_len == 0) { > + return (void *)hay; > + } > + > + if (hay_len < s_len) { > + return NULL; > + } > + > + if (s_len == 1) { > + return memchr(hay, s[0], hay_len); > + } Why special-case length 1? > + > + for (; hay <= last; hay++) { > + if (hay[0] == s[0] && memcmp(hay, s, s_len) == 0) { Why not just memcmp()? > + return (void *)hay; > + } > + } > + > + return NULL; > +}
diff --git a/configure b/configure index 409edf9..9e04269 100755 --- a/configure +++ b/configure @@ -3091,6 +3091,17 @@ if compile_prog "" "" ; then fi ########################################## +# memmem probe +cat > $TMPC <<EOF +#include <string.h> +int main(int argc, char *argv[]) { return memmem(argv[0], 0, argv[0], 0) != argv[0]; } +EOF +memmem=no +if compile_prog "" "" ; then + memmem=yes +fi + +########################################## # fdt probe # fdt support is mandatory for at least some target architectures, # so insist on it if we're building those system emulators. @@ -4473,6 +4484,7 @@ echo "RDMA support $rdma" echo "TCG interpreter $tcg_interpreter" echo "fdt support $fdt" echo "preadv support $preadv" +echo "memmem support $memmem" echo "fdatasync $fdatasync" echo "madvise $madvise" echo "posix_madvise $posix_madvise" @@ -4822,6 +4834,9 @@ fi if test "$preadv" = "yes" ; then echo "CONFIG_PREADV=y" >> $config_host_mak fi +if test "$memmem" = "yes" ; then + echo "CONFIG_MEMMEM=y" >> $config_host_mak +fi if test "$fdt" = "yes" ; then echo "CONFIG_FDT=y" >> $config_host_mak fi diff --git a/include/qemu/osdep.h b/include/qemu/osdep.h index 3247364..abc5486 100644 --- a/include/qemu/osdep.h +++ b/include/qemu/osdep.h @@ -201,6 +201,10 @@ ssize_t writev(int fd, const struct iovec *iov, int iov_cnt); #include <sys/uio.h> #endif +#ifndef CONFIG_MEMMEM +void *memmem(const void *hay, size_t hay_len, const void *s, size_t s_len); +#endif /* !CONFIG_MEMMEM */ + #ifdef _WIN32 static inline void qemu_timersub(const struct timeval *val1, const struct timeval *val2, diff --git a/util/Makefile.objs b/util/Makefile.objs index ceaba30..628242f 100644 --- a/util/Makefile.objs +++ b/util/Makefile.objs @@ -1,6 +1,7 @@ util-obj-y = osdep.o cutils.o unicode.o qemu-timer-common.o util-obj-$(CONFIG_WIN32) += oslib-win32.o qemu-thread-win32.o event_notifier-win32.o util-obj-$(CONFIG_POSIX) += oslib-posix.o qemu-thread-posix.o event_notifier-posix.o qemu-openpty.o +util-obj-$(call lnot,$(CONFIG_MEMMEM)) += memmem.o util-obj-y += envlist.o path.o module.o util-obj-$(call lnot,$(CONFIG_INT128)) += host-utils.o util-obj-y += bitmap.o bitops.o hbitmap.o diff --git a/util/memmem.c b/util/memmem.c new file mode 100644 index 0000000..16ac611 --- /dev/null +++ b/util/memmem.c @@ -0,0 +1,63 @@ +/* + * memmem replacement function + * + * Copyright (C) 2015 Huawei Technologies Duesseldorf GmbH + * Written by Claudio Fontana <claudio.fontana@huawei.com> + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ + +#include <qemu-common.h> + +/* + * Search for the first occurrence of a binary string ("needle") + * in a memory region ("haystack"). + * + * If needle length is 0, it returns the pointer to the haystack. + * Otherwise it returns the pointer to the first character of the first + * occurrence of the needle in the haystack, or NULL if none are found. + * + */ +void * +memmem(const void *haystack, size_t hay_len, const void *needle, size_t s_len) +{ + const unsigned char *hay = (const unsigned char *)haystack; + const unsigned char *s = (const unsigned char *)needle; + const unsigned char *last = hay + (hay_len - s_len); + + if (s_len == 0) { + return (void *)hay; + } + + if (hay_len < s_len) { + return NULL; + } + + if (s_len == 1) { + return memchr(hay, s[0], hay_len); + } + + for (; hay <= last; hay++) { + if (hay[0] == s[0] && memcmp(hay, s, s_len) == 0) { + return (void *)hay; + } + } + + return NULL; +}