| Message ID | 1f6bc60305b8c1cd00f5e2a361a05d7b4bc56338.1527814874.git.keno@juliacomputing.com |
|---|---|
| State | New |
| Headers | show |
| Series | 9p: Add support for Darwin | expand |
On Thu, 31 May 2018 21:25:56 -0400 Keno Fischer <keno@juliacomputing.com> wrote: > strchrnul is a GNU extension and thus unavailable on a number of targets. > In the review for a commit removing strchrnul from 9p, I was asked to > create a qemu_strchrnul helper to factor out this functionality. > Do so, and use it in a number of other places in the code base that inlined > the replacement pattern in a place where strchrnul could be used. > > Signed-off-by: Keno Fischer <keno@juliacomputing.com> > --- > And possibly we could detect in configure if the host has strchrnul() and use it, but this optimization can be done later. I haven't checked if there could be other candidates in the current code base though. Also, this patch touches some other subsystems, so I'm Cc'ing to the other maintainers as reported by ./scripts/get_maintainer.pl: Greg Kurz <groug@kaod.org> (supporter:virtio-9p) Markus Armbruster <armbru@redhat.com> (supporter:QMP) "Dr. David Alan Gilbert" <dgilbert@redhat.com> (maintainer:Human Monitor (HMP)) qemu-devel@nongnu.org (open list:All patches CC here) Anyway, Acked-by: Greg Kurz <groug@kaod.org> > Changes since v1: New patch > > hw/9pfs/9p-local.c | 2 +- > include/qemu/cutils.h | 1 + > monitor.c | 8 ++------ > util/cutils.c | 13 +++++++++++++ > util/qemu-option.c | 6 +----- > util/uri.c | 6 ++---- > 6 files changed, 20 insertions(+), 16 deletions(-) > > diff --git a/hw/9pfs/9p-local.c b/hw/9pfs/9p-local.c > index b37b1db..bcf2798 100644 > --- a/hw/9pfs/9p-local.c > +++ b/hw/9pfs/9p-local.c > @@ -65,7 +65,7 @@ int local_open_nofollow(FsContext *fs_ctx, const char *path, int flags, > assert(*path != '/'); > > head = g_strdup(path); > - c = strchrnul(path, '/'); > + c = qemu_strchrnul(path, '/'); > if (*c) { > /* Intermediate path element */ > head[c - path] = 0; > diff --git a/include/qemu/cutils.h b/include/qemu/cutils.h > index a663340..bc40c30 100644 > --- a/include/qemu/cutils.h > +++ b/include/qemu/cutils.h > @@ -122,6 +122,7 @@ int qemu_strnlen(const char *s, int max_len); > * Returns: the pointer originally in @input. > */ > char *qemu_strsep(char **input, const char *delim); > +const char *qemu_strchrnul(const char *s, int c); > time_t mktimegm(struct tm *tm); > int qemu_fdatasync(int fd); > int fcntl_setfl(int fd, int flag); > diff --git a/monitor.c b/monitor.c > index 922cfc0..e1f01c4 100644 > --- a/monitor.c > +++ b/monitor.c > @@ -798,9 +798,7 @@ static int compare_cmd(const char *name, const char *list) > p = list; > for(;;) { > pstart = p; > - p = strchr(p, '|'); > - if (!p) > - p = pstart + strlen(pstart); > + p = qemu_strchrnul(p, '|'); > if ((p - pstart) == len && !memcmp(pstart, name, len)) > return 1; > if (*p == '\0') > @@ -3401,9 +3399,7 @@ static void cmd_completion(Monitor *mon, const char *name, const char *list) > p = list; > for(;;) { > pstart = p; > - p = strchr(p, '|'); > - if (!p) > - p = pstart + strlen(pstart); > + p = qemu_strchrnul(p, '|'); > len = p - pstart; > if (len > sizeof(cmd) - 2) > len = sizeof(cmd) - 2; > diff --git a/util/cutils.c b/util/cutils.c > index 0de69e6..6e078b0 100644 > --- a/util/cutils.c > +++ b/util/cutils.c > @@ -545,6 +545,19 @@ int qemu_strtou64(const char *nptr, const char **endptr, int base, > } > > /** > + * Searches for the first occurrence of 'c' in 's', and returns a pointer > + * to the trailing null byte if none was found. > + */ > +const char *qemu_strchrnul(const char *s, int c) > +{ > + const char *e = strchr(s, c); > + if (!e) { > + e = s + strlen(s); > + } > + return e; > +} > + > +/** > * parse_uint: > * > * @s: String to parse > diff --git a/util/qemu-option.c b/util/qemu-option.c > index 58d1c23..54eca12 100644 > --- a/util/qemu-option.c > +++ b/util/qemu-option.c > @@ -77,11 +77,7 @@ const char *get_opt_value(const char *p, char **value) > > *value = NULL; > while (1) { > - offset = strchr(p, ','); > - if (!offset) { > - offset = p + strlen(p); > - } > - > + offset = qemu_strchrnul(p, ','); > length = offset - p; > if (*offset != '\0' && *(offset + 1) == ',') { > length++; > diff --git a/util/uri.c b/util/uri.c > index 8624a7a..8bdef84 100644 > --- a/util/uri.c > +++ b/util/uri.c > @@ -52,6 +52,7 @@ > */ > > #include "qemu/osdep.h" > +#include "qemu/cutils.h" > > #include "qemu/uri.h" > > @@ -2266,10 +2267,7 @@ struct QueryParams *query_params_parse(const char *query) > /* Find the next separator, or end of the string. */ > end = strchr(query, '&'); > if (!end) { > - end = strchr(query, ';'); > - } > - if (!end) { > - end = query + strlen(query); > + end = qemu_strchrnul(query, ';'); > } > > /* Find the first '=' character between here and end. */
* Greg Kurz (groug@kaod.org) wrote: > On Thu, 31 May 2018 21:25:56 -0400 > Keno Fischer <keno@juliacomputing.com> wrote: > > > strchrnul is a GNU extension and thus unavailable on a number of targets. > > In the review for a commit removing strchrnul from 9p, I was asked to > > create a qemu_strchrnul helper to factor out this functionality. > > Do so, and use it in a number of other places in the code base that inlined > > the replacement pattern in a place where strchrnul could be used. > > > > Signed-off-by: Keno Fischer <keno@juliacomputing.com> > > --- > > > > And possibly we could detect in configure if the host has strchrnul() and > use it, but this optimization can be done later. > > I haven't checked if there could be other candidates in the current code > base though. Also, this patch touches some other subsystems, so I'm Cc'ing > to the other maintainers as reported by ./scripts/get_maintainer.pl: That looks fine from my point of view; I can see you could probably also use it in the code at the start of the while loop in hmp_sendkey: while (1) { separator = strchr(keys, '-'); keyname_len = separator ? separator - keys : strlen(keys); Dave > Greg Kurz <groug@kaod.org> (supporter:virtio-9p) > Markus Armbruster <armbru@redhat.com> (supporter:QMP) > "Dr. David Alan Gilbert" <dgilbert@redhat.com> (maintainer:Human Monitor (HMP)) > qemu-devel@nongnu.org (open list:All patches CC here) > > Anyway, > > Acked-by: Greg Kurz <groug@kaod.org> > > > Changes since v1: New patch > > > > hw/9pfs/9p-local.c | 2 +- > > include/qemu/cutils.h | 1 + > > monitor.c | 8 ++------ > > util/cutils.c | 13 +++++++++++++ > > util/qemu-option.c | 6 +----- > > util/uri.c | 6 ++---- > > 6 files changed, 20 insertions(+), 16 deletions(-) > > > > diff --git a/hw/9pfs/9p-local.c b/hw/9pfs/9p-local.c > > index b37b1db..bcf2798 100644 > > --- a/hw/9pfs/9p-local.c > > +++ b/hw/9pfs/9p-local.c > > @@ -65,7 +65,7 @@ int local_open_nofollow(FsContext *fs_ctx, const char *path, int flags, > > assert(*path != '/'); > > > > head = g_strdup(path); > > - c = strchrnul(path, '/'); > > + c = qemu_strchrnul(path, '/'); > > if (*c) { > > /* Intermediate path element */ > > head[c - path] = 0; > > diff --git a/include/qemu/cutils.h b/include/qemu/cutils.h > > index a663340..bc40c30 100644 > > --- a/include/qemu/cutils.h > > +++ b/include/qemu/cutils.h > > @@ -122,6 +122,7 @@ int qemu_strnlen(const char *s, int max_len); > > * Returns: the pointer originally in @input. > > */ > > char *qemu_strsep(char **input, const char *delim); > > +const char *qemu_strchrnul(const char *s, int c); > > time_t mktimegm(struct tm *tm); > > int qemu_fdatasync(int fd); > > int fcntl_setfl(int fd, int flag); > > diff --git a/monitor.c b/monitor.c > > index 922cfc0..e1f01c4 100644 > > --- a/monitor.c > > +++ b/monitor.c > > @@ -798,9 +798,7 @@ static int compare_cmd(const char *name, const char *list) > > p = list; > > for(;;) { > > pstart = p; > > - p = strchr(p, '|'); > > - if (!p) > > - p = pstart + strlen(pstart); > > + p = qemu_strchrnul(p, '|'); > > if ((p - pstart) == len && !memcmp(pstart, name, len)) > > return 1; > > if (*p == '\0') > > @@ -3401,9 +3399,7 @@ static void cmd_completion(Monitor *mon, const char *name, const char *list) > > p = list; > > for(;;) { > > pstart = p; > > - p = strchr(p, '|'); > > - if (!p) > > - p = pstart + strlen(pstart); > > + p = qemu_strchrnul(p, '|'); > > len = p - pstart; > > if (len > sizeof(cmd) - 2) > > len = sizeof(cmd) - 2; > > diff --git a/util/cutils.c b/util/cutils.c > > index 0de69e6..6e078b0 100644 > > --- a/util/cutils.c > > +++ b/util/cutils.c > > @@ -545,6 +545,19 @@ int qemu_strtou64(const char *nptr, const char **endptr, int base, > > } > > > > /** > > + * Searches for the first occurrence of 'c' in 's', and returns a pointer > > + * to the trailing null byte if none was found. > > + */ > > +const char *qemu_strchrnul(const char *s, int c) > > +{ > > + const char *e = strchr(s, c); > > + if (!e) { > > + e = s + strlen(s); > > + } > > + return e; > > +} > > + > > +/** > > * parse_uint: > > * > > * @s: String to parse > > diff --git a/util/qemu-option.c b/util/qemu-option.c > > index 58d1c23..54eca12 100644 > > --- a/util/qemu-option.c > > +++ b/util/qemu-option.c > > @@ -77,11 +77,7 @@ const char *get_opt_value(const char *p, char **value) > > > > *value = NULL; > > while (1) { > > - offset = strchr(p, ','); > > - if (!offset) { > > - offset = p + strlen(p); > > - } > > - > > + offset = qemu_strchrnul(p, ','); > > length = offset - p; > > if (*offset != '\0' && *(offset + 1) == ',') { > > length++; > > diff --git a/util/uri.c b/util/uri.c > > index 8624a7a..8bdef84 100644 > > --- a/util/uri.c > > +++ b/util/uri.c > > @@ -52,6 +52,7 @@ > > */ > > > > #include "qemu/osdep.h" > > +#include "qemu/cutils.h" > > > > #include "qemu/uri.h" > > > > @@ -2266,10 +2267,7 @@ struct QueryParams *query_params_parse(const char *query) > > /* Find the next separator, or end of the string. */ > > end = strchr(query, '&'); > > if (!end) { > > - end = strchr(query, ';'); > > - } > > - if (!end) { > > - end = query + strlen(query); > > + end = qemu_strchrnul(query, ';'); > > } > > > > /* Find the first '=' character between here and end. */ > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
On 05/31/2018 08:25 PM, Keno Fischer wrote: > strchrnul is a GNU extension and thus unavailable on a number of targets. > In the review for a commit removing strchrnul from 9p, I was asked to > create a qemu_strchrnul helper to factor out this functionality. > Do so, and use it in a number of other places in the code base that inlined > the replacement pattern in a place where strchrnul could be used. > > Signed-off-by: Keno Fischer <keno@juliacomputing.com> > --- > > +++ b/util/cutils.c > @@ -545,6 +545,19 @@ int qemu_strtou64(const char *nptr, const char **endptr, int base, > } > > /** > + * Searches for the first occurrence of 'c' in 's', and returns a pointer > + * to the trailing null byte if none was found. > + */ > +const char *qemu_strchrnul(const char *s, int c) > +{ > + const char *e = strchr(s, c); > + if (!e) { > + e = s + strlen(s); > + } > + return e; > +} This is twice as slow on glibc systems when the pointer to NUL is returned (because it has to traverse the string twice); it's better to have a configure check for whether strchrnul exists, and if so, use that directly.
diff --git a/hw/9pfs/9p-local.c b/hw/9pfs/9p-local.c index b37b1db..bcf2798 100644 --- a/hw/9pfs/9p-local.c +++ b/hw/9pfs/9p-local.c @@ -65,7 +65,7 @@ int local_open_nofollow(FsContext *fs_ctx, const char *path, int flags, assert(*path != '/'); head = g_strdup(path); - c = strchrnul(path, '/'); + c = qemu_strchrnul(path, '/'); if (*c) { /* Intermediate path element */ head[c - path] = 0; diff --git a/include/qemu/cutils.h b/include/qemu/cutils.h index a663340..bc40c30 100644 --- a/include/qemu/cutils.h +++ b/include/qemu/cutils.h @@ -122,6 +122,7 @@ int qemu_strnlen(const char *s, int max_len); * Returns: the pointer originally in @input. */ char *qemu_strsep(char **input, const char *delim); +const char *qemu_strchrnul(const char *s, int c); time_t mktimegm(struct tm *tm); int qemu_fdatasync(int fd); int fcntl_setfl(int fd, int flag); diff --git a/monitor.c b/monitor.c index 922cfc0..e1f01c4 100644 --- a/monitor.c +++ b/monitor.c @@ -798,9 +798,7 @@ static int compare_cmd(const char *name, const char *list) p = list; for(;;) { pstart = p; - p = strchr(p, '|'); - if (!p) - p = pstart + strlen(pstart); + p = qemu_strchrnul(p, '|'); if ((p - pstart) == len && !memcmp(pstart, name, len)) return 1; if (*p == '\0') @@ -3401,9 +3399,7 @@ static void cmd_completion(Monitor *mon, const char *name, const char *list) p = list; for(;;) { pstart = p; - p = strchr(p, '|'); - if (!p) - p = pstart + strlen(pstart); + p = qemu_strchrnul(p, '|'); len = p - pstart; if (len > sizeof(cmd) - 2) len = sizeof(cmd) - 2; diff --git a/util/cutils.c b/util/cutils.c index 0de69e6..6e078b0 100644 --- a/util/cutils.c +++ b/util/cutils.c @@ -545,6 +545,19 @@ int qemu_strtou64(const char *nptr, const char **endptr, int base, } /** + * Searches for the first occurrence of 'c' in 's', and returns a pointer + * to the trailing null byte if none was found. + */ +const char *qemu_strchrnul(const char *s, int c) +{ + const char *e = strchr(s, c); + if (!e) { + e = s + strlen(s); + } + return e; +} + +/** * parse_uint: * * @s: String to parse diff --git a/util/qemu-option.c b/util/qemu-option.c index 58d1c23..54eca12 100644 --- a/util/qemu-option.c +++ b/util/qemu-option.c @@ -77,11 +77,7 @@ const char *get_opt_value(const char *p, char **value) *value = NULL; while (1) { - offset = strchr(p, ','); - if (!offset) { - offset = p + strlen(p); - } - + offset = qemu_strchrnul(p, ','); length = offset - p; if (*offset != '\0' && *(offset + 1) == ',') { length++; diff --git a/util/uri.c b/util/uri.c index 8624a7a..8bdef84 100644 --- a/util/uri.c +++ b/util/uri.c @@ -52,6 +52,7 @@ */ #include "qemu/osdep.h" +#include "qemu/cutils.h" #include "qemu/uri.h" @@ -2266,10 +2267,7 @@ struct QueryParams *query_params_parse(const char *query) /* Find the next separator, or end of the string. */ end = strchr(query, '&'); if (!end) { - end = strchr(query, ';'); - } - if (!end) { - end = query + strlen(query); + end = qemu_strchrnul(query, ';'); } /* Find the first '=' character between here and end. */
strchrnul is a GNU extension and thus unavailable on a number of targets. In the review for a commit removing strchrnul from 9p, I was asked to create a qemu_strchrnul helper to factor out this functionality. Do so, and use it in a number of other places in the code base that inlined the replacement pattern in a place where strchrnul could be used. Signed-off-by: Keno Fischer <keno@juliacomputing.com> --- Changes since v1: New patch hw/9pfs/9p-local.c | 2 +- include/qemu/cutils.h | 1 + monitor.c | 8 ++------ util/cutils.c | 13 +++++++++++++ util/qemu-option.c | 6 +----- util/uri.c | 6 ++---- 6 files changed, 20 insertions(+), 16 deletions(-)