On Thu, Feb 18, 2021 at 12:15:36PM -0800, Doug Evans wrote: > The parsing is moved into new function inet_parse_host_and_port. > This is done in preparation for using the function in net/slirp.c. > > Signed-off-by: Doug Evans <d...@google.com> > --- > > Changes from v3: > - this patch is new in v4 > - provides new utility: inet_parse_host_and_port, updates inet_parse > to use it > > include/qemu/sockets.h | 3 ++ > util/qemu-sockets.c | 94 +++++++++++++++++++++++++++++++----------- > 2 files changed, 72 insertions(+), 25 deletions(-) > > diff --git a/include/qemu/sockets.h b/include/qemu/sockets.h > index 7d1f813576..f720378a6b 100644 > --- a/include/qemu/sockets.h > +++ b/include/qemu/sockets.h > @@ -31,6 +31,9 @@ int socket_set_fast_reuse(int fd); > > int inet_ai_family_from_address(InetSocketAddress *addr, > Error **errp); > +const char* inet_parse_host_and_port(const char* str, int terminator, > + char **addr, char **port, bool *is_v6, > + Error **errp); > int inet_parse(InetSocketAddress *addr, const char *str, Error **errp); > int inet_connect(const char *str, Error **errp); > int inet_connect_saddr(InetSocketAddress *saddr, Error **errp); > diff --git a/util/qemu-sockets.c b/util/qemu-sockets.c > index 8af0278f15..9fca7d9212 100644 > --- a/util/qemu-sockets.c > +++ b/util/qemu-sockets.c > @@ -615,44 +615,88 @@ static int inet_parse_flag(const char *flagname, const > char *optstr, bool *val, > return 0; > } > > -int inet_parse(InetSocketAddress *addr, const char *str, Error **errp) > +/* > + * Parse an inet host and port as "host:port<terminator>". > + * Terminator may be '\0'. > + * The syntax for ipv4 addresses is: address:port. > + * The syntax for ipv6 addresses is: [address]:port.
It also supports "The syntax for hostnames is hostname:port > + * On success, returns a pointer to the terminator. Space for the address and > + * port is malloced and stored in *host, *port, the caller must free. > + * *is_v6 indicates whether the address is ipv4 or ipv6. If ipv6 then the > + * surrounding [] brackets are removed. When is_v6 is true, it indicates that a numeric ipv6 address was given. When false either a numberic ipv4 address or hostname was given. > + * On failure NULL is returned with the error stored in *errp. > + */ > +const char* inet_parse_host_and_port(const char* str, int terminator, > + char **hostp, char **portp, bool *is_v6, > + Error **errp) > { > - const char *optstr, *h; > + const char *terminator_ptr = strchr(str, terminator); > + g_autofree char *buf = NULL; > char host[65]; > char port[33]; > - int to; > - int pos; > - char *begin; > > - memset(addr, 0, sizeof(*addr)); > + if (terminator_ptr == NULL) { > + /* If the terminator isn't found then use the entire string. */ > + terminator_ptr = str + strlen(str); > + } > + buf = g_strndup(str, terminator_ptr - str); > > - /* parse address */ > - if (str[0] == ':') { > - /* no host given */ > - host[0] = '\0'; > - if (sscanf(str, ":%32[^,]%n", port, &pos) != 1) { > - error_setg(errp, "error parsing port in address '%s'", str); > - return -1; > - } > - } else if (str[0] == '[') { > + if (buf[0] == '[') { > /* IPv6 addr */ > - if (sscanf(str, "[%64[^]]]:%32[^,]%n", host, port, &pos) != 2) { > - error_setg(errp, "error parsing IPv6 address '%s'", str); > - return -1; > + if (buf[1] == ']') { > + /* sscanf %[ doesn't recognize empty contents. */ > + host[0] = '\0'; > + if (sscanf(buf, "[]:%32s", port) != 1) { > + error_setg(errp, "error parsing IPv6 host:port '%s'", buf); > + return NULL; > + } This is introducing new functionality to the parser. Current callers let empty string ":port" be used for both ipv4 and ipv6, based on whether the flags ",ipv4[=on|off],ipv6[=on|off]" later follow. I presume you want an explicit way to represent an empty ipv6 hostname to avoid changing semantics for existing slirp CLI args, where the existing ":port" exclusively means ipv4. IIC, this is also why you needed to introduce the "is_v6" flag, because any non-empty address can be reliably parsed without needing this flag. This is reasonable, but any such functional change should be in a separate commit from refactoring. IOW, remove this and the is_v6 flag, and add them in a separate patch to explain to the need for new functionality in the parsing. Given that existing callers don't need to support "[]", we should not let that be parsed, unless the caller passing a "is_v6" pointer which is not NULL. > + } else { > + if (sscanf(buf, "[%64[^]]]:%32s", host, port) != 2) { > + error_setg(errp, "error parsing IPv6 host:port '%s'", buf); > + return NULL; > + } > } > } else { > - /* hostname or IPv4 addr */ > - if (sscanf(str, "%64[^:]:%32[^,]%n", host, port, &pos) != 2) { > - error_setg(errp, "error parsing address '%s'", str); > - return -1; > + if (buf[0] == ':') { > + /* no host given */ > + host[0] = '\0'; > + if (sscanf(buf, ":%32s", port) != 1) { > + error_setg(errp, "error parsing host:port '%s'", buf); > + return NULL; > + } It would be preferreable if the parsing code was not re-ordered when extracting it. It doesn't look like a functional change, but I'm unsure why you moved it ? > + } else { > + /* hostname or IPv4 addr */ > + if (sscanf(buf, "%64[^:]:%32s", host, port) != 2) { > + error_setg(errp, "error parsing host:port '%s'", buf); > + return NULL; > + } > } > } > > - addr->host = g_strdup(host); > - addr->port = g_strdup(port); > + *hostp = g_strdup(host); > + *portp = g_strdup(port); > + *is_v6 = buf[0] == '['; > + > + return terminator_ptr; > +} > + > +int inet_parse(InetSocketAddress *addr, const char *str, Error **errp) > +{ > + const char *optstr, *h; > + bool is_v6; > + int to; > + int pos; > + char *begin; > + > + memset(addr, 0, sizeof(*addr)); > + > + optstr = inet_parse_host_and_port(str, ',', &addr->host, &addr->port, > + &is_v6, errp); Just pass NULL since we don't need is_v6 > + if (optstr == NULL) { > + return -1; > + } > > /* parse options */ > - optstr = str + pos; > h = strstr(optstr, ",to="); > if (h) { > h += 4; > -- > 2.30.0.617.g56c4b15f3c-goog > Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|