Chip types can no longer contain dashes. This makes it possible to
rewrite sensors_parse_chip_name() with a simpler algorithm. The new
code is smaller by about one third, and twice as fast on average
(5 times as fast in the most frequent case "foo-*".)
---
lib/data.c | 152 +++++++++++++++++++++++-----------------------------
lib/sensors.conf.5 | 16 +----
2 files changed, 74 insertions(+), 94 deletions(-)
--- lm-sensors-3.orig/lib/data.c 2007-08-15 16:21:16.000000000 +0200
+++ lm-sensors-3/lib/data.c 2007-08-15 16:22:03.000000000 +0200
@@ -1,6 +1,7 @@
/*
data.c - Part of libsensors, a Linux library for reading sensor data.
Copyright (c) 1998, 1999 Frodo Looijaard <frodol at dds.nl>
+ Copyright (C) 2007 Jean Delvare <khali at linux-fr.org>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
@@ -17,6 +18,9 @@
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
+/* this define needed for strndup() */
+#define _GNU_SOURCE
+
#include <stdlib.h>
#include <string.h>
@@ -46,8 +50,8 @@ int sensors_proc_bus_max = 0;
static int sensors_substitute_chip(sensors_chip_name *name,int lineno);
-/* Wow, this must be one of the ugliest functions I have ever written.
- The idea is that it parses a chip name. These are valid names:
+/*
+ Parse a chip name to the internal representation. These are valid names:
lm78-i2c-10-5e *-i2c-10-5e
lm78-i2c-10-* *-i2c-10-*
@@ -56,103 +60,85 @@ static int sensors_substitute_chip(senso
lm78-isa-10dd *-isa-10dd
lm78-isa-* *-isa-*
lm78-* *-*
- *
- Here 'lm78' can be any prefix. To complicate matters, such a prefix
- can also contain dashes (like lm78-j, for example!). 'i2c' and 'isa' are
+
+ Here 'lm78' can be any prefix. 'i2c' and 'isa' are
literal strings, just like all dashes '-' and wildcards '*'. '10' can
be any decimal i2c bus number. '5e' can be any hexadecimal i2c device
address, and '10dd' any hexadecimal isa address.
- If '*' is used in prefixes, together with dashes, ambigious parses are
- introduced. In that case, the prefix is kept as small as possible.
-
The 'prefix' part in the result is freshly allocated. All old contents
of res is overwritten. res itself is not allocated. In case of an error
return (ie. != 0), res is undefined, but all allocations are undone.
-
- Don't tell me there are bugs in here, because I'll start screaming :-)
*/
-int sensors_parse_chip_name(const char *orig_name, sensors_chip_name *res)
+int sensors_parse_chip_name(const char *name, sensors_chip_name *res)
{
- char *part2, *part3, *part4;
- char *name = strdup(orig_name);
- char *endptr;
+ char *dash;
- if (! name)
- sensors_fatal_error("sensors_parse_chip_name","Allocating new name");
- /* First split name in upto four pieces. */
- if ((part4 = strrchr(name,'-')))
- *part4++ = '\0';
- if ((part3 = strrchr(name,'-')))
- *part3++ = '\0';
- if ((part2 = strrchr(name,'-')))
- *part2++ = '\0';
-
- /* No dashes found? */
- if (! part4) {
- if (!strcmp(name,"*")) {
- res->prefix = SENSORS_CHIP_NAME_PREFIX_ANY;
- res->bus = SENSORS_CHIP_NAME_BUS_ANY;
- res->addr = SENSORS_CHIP_NAME_ADDR_ANY;
- goto SUCCES;
- } else
- goto ERROR;
- }
+ /* First, the prefix. It's either "*" or a real chip name. */
+ if (!strncmp(name, "*-", 2)) {
+ res->prefix = SENSORS_CHIP_NAME_PREFIX_ANY;
+ name += 2;
+ } else {
+ if (!(dash = strchr(name, '-')))
+ return -SENSORS_ERR_CHIP_NAME;
+ res->prefix = strndup(name, dash - name);
+ if (!res->prefix)
+ sensors_fatal_error("sensors_parse_chip_name",
+ "Allocating name prefix");
+ name = dash + 1;
+ }
- /* At least one dash found. Now part4 is either '*', or an address */
- if (!strcmp(part4,"*"))
- res->addr = SENSORS_CHIP_NAME_ADDR_ANY;
- else {
- res->addr = strtoul(part4, &endptr, 16);
- if (*part4 == '\0' || *endptr != '\0' || res->addr < 0)
- goto ERROR;
- }
+ /* Then we have either a sole "*" (all chips with this name) or a bus
+ type and an address. */
+ if (!strcmp(name, "*")) {
+ res->bus = SENSORS_CHIP_NAME_BUS_ANY;
+ res->addr = SENSORS_CHIP_NAME_ADDR_ANY;
+ return 0;
+ }
- /* OK. So let's look at part3. It must either be the number of the
- i2c bus (and then part2 *must* be "i2c"), or it must be "isa",
- or, if part4 was "*", it belongs to 'prefix'. Or no second dash
- was found at all, of course. */
- if (! part3) {
- if (res->addr == SENSORS_CHIP_NAME_ADDR_ANY) {
- res->bus = SENSORS_CHIP_NAME_BUS_ANY;
- } else
- goto ERROR;
- } else if (!strcmp(part3,"isa")) {
- res->bus = SENSORS_CHIP_NAME_BUS_ISA;
- if (part2)
- *(part2-1) = '-';
- } else if (!strcmp(part3,"pci")) {
- res->bus = SENSORS_CHIP_NAME_BUS_PCI;
- if (part2)
- *(part2-1) = '-';
- } else if (part2 && !strcmp(part2,"i2c") && !strcmp(part3,"*"))
- res->bus = SENSORS_CHIP_NAME_BUS_ANY_I2C;
- else if (part2 && !strcmp(part2,"i2c")) {
- res->bus = strtoul(part3, &endptr, 10);
- if (*part3 == '\0' || *endptr != '\0' || res->bus < 0)
- goto ERROR;
- } else if (res->addr == SENSORS_CHIP_NAME_ADDR_ANY) {
- res->bus = SENSORS_CHIP_NAME_BUS_ANY;
- if (part2)
- *(part2-1) = '-';
- *(part3-1) = '-';
- } else
- goto ERROR;
-
- if (!strcmp(name,"*"))
- res->prefix = SENSORS_CHIP_NAME_PREFIX_ANY;
- else if (! (res->prefix = strdup(name)))
- sensors_fatal_error("sensors_parse_chip_name","Allocating new name");
- goto SUCCES;
+ if (!(dash = strchr(name, '-')))
+ goto ERROR;
+ if (!strncmp(name, "i2c", dash - name))
+ res->bus = SENSORS_CHIP_NAME_BUS_ANY_I2C;
+ else if (!strncmp(name, "isa", dash - name))
+ res->bus = SENSORS_CHIP_NAME_BUS_ISA;
+ else if (!strncmp(name, "pci", dash - name))
+ res->bus = SENSORS_CHIP_NAME_BUS_PCI;
+ else
+ goto ERROR;
+ name = dash + 1;
+
+ /* Some bus types (i2c) have an additional bus number. For these, the
+ next part is either a "*" (any bus of that type) or a decimal
+ number. */
+ switch (res->bus) {
+ case SENSORS_CHIP_NAME_BUS_ANY_I2C:
+ if (!strncmp(name, "*-", 2)) {
+ name += 2;
+ break;
+ }
+
+ res->bus = strtoul(name, &dash, 10);
+ if (*name == '\0' || *dash != '-' || res->bus < 0)
+ goto ERROR;
+ name = dash + 1;
+ }
-SUCCES:
- free(name);
- return 0;
+ /* Last part is the chip address, or "*" for any address. */
+ if (!strcmp(name, "*")) {
+ res->addr = SENSORS_CHIP_NAME_ADDR_ANY;
+ } else {
+ res->addr = strtoul(name, &dash, 16);
+ if (*name == '\0' || *dash != '\0' || res->addr < 0)
+ goto ERROR;
+ }
+
+ return 0;
ERROR:
- free(name);
- return -SENSORS_ERR_CHIP_NAME;
+ free(res->prefix);
+ return -SENSORS_ERR_CHIP_NAME;
}
int sensors_snprintf_chip_name(char *str, size_t size,
--- lm-sensors-3.orig/lib/sensors.conf.5 2007-06-25 16:12:05.000000000 +0200
+++ lm-sensors-3/lib/sensors.conf.5 2007-08-15 16:52:05.000000000 +0200
@@ -186,9 +186,7 @@ statement is ignored upto the next
statement.
A chip description is built from a couple of elements, separated by
-dashes. To complicate matters, sometimes an element can also contain
-dashes. This complicates the parsing algorithm, but is not too confusing
-for humans (we hope!).
+dashes.
The first element is the name of the chip type. Sometimes a single driver
implements several chip types, with several names. The driver documentation
@@ -216,10 +214,10 @@ the wildcard operator
.I *
for this element.
-There are some folding rules for wildcards to make things easier for humans
-to read. Also, you can't specify the address if you wildcard the complete
-second element. The following are all valid chip type specification based
-on
+Note that it wouldn't make any sense to specify the address without the
+bus type. For this reason, the address part is plain omitted when the bus
+type isn't specified.
+The following are all valid chip type specification based on
.I lm78\-i2c\-1\-2d
or
.IR lm78\-isa\-0290 :
@@ -250,10 +248,6 @@ lm78\-*
*\-isa\-0290
.sp 0
*\-isa\-*
-.sp 0
-*\-*
-.sp 0
-*
.RE
.SS COMPUTE STATEMENT
--
Jean Delvare
