tree-wide: convert open calls to remove spaces to skip_spaces() lib function

Makes use of skip_spaces() defined in lib/string.c for removing leading
spaces from strings all over the tree.

It decreases lib.a code size by 47 bytes and reuses the function tree-wide:
   text    data     bss     dec     hex filename
  64688     584     592   65864   10148 (TOTALS-BEFORE)
  64641     584     592   65817   10119 (TOTALS-AFTER)

Also, while at it, if we see (*str && isspace(*str)), we can be sure to
remove the first condition (*str) as the second one (isspace(*str)) also
evaluates to 0 whenever *str == 0, making it redundant. In other words,
"a char equals zero is never a space".

Julia Lawall tried the semantic patch (http://coccinelle.lip6.fr) below,
and found occurrences of this pattern on 3 more files:
    drivers/leds/led-class.c
    drivers/leds/ledtrig-timer.c
    drivers/video/output.c

@@
expression str;
@@

( // ignore skip_spaces cases
while (*str &&  isspace(*str)) { \(str++;\|++str;\) }
|
- *str &&
isspace(*str)
)

Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com>
Cc: Julia Lawall <julia@diku.dk>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Neil Brown <neilb@suse.de>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: David Howells <dhowells@redhat.com>
Cc: <linux-ext4@vger.kernel.org>
Cc: Samuel Ortiz <samuel@sortiz.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 10 insertions, 26 deletions

diff --git a/drivers/pnp/interface.c b/drivers/pnp/interface.c
index c3f1c8e9d254..68b0c04987e4 100644
--- a/drivers/pnp/interface.c
+++ b/drivers/pnp/interface.c
@@ -310,8 +310,7 @@ static ssize_t pnp_set_current_resources(struct device *dmdev,
                 goto done;
         }
 
-        while (isspace(*buf))
-                ++buf;
+        buf = skip_spaces(buf);
         if (!strnicmp(buf, "disable", 7)) {
                 retval = pnp_disable_dev(dev);
                 goto done;
@@ -353,19 +352,13 @@ static ssize_t pnp_set_current_resources(struct device *dmdev,
                 pnp_init_resources(dev);
                 mutex_lock(&pnp_res_mutex);
                 while (1) {
-                        while (isspace(*buf))
-                                ++buf;
+                        buf = skip_spaces(buf);
                         if (!strnicmp(buf, "io", 2)) {
-                                buf += 2;
-                                while (isspace(*buf))
-                                        ++buf;
+                                buf = skip_spaces(buf + 2);
                                 start = simple_strtoul(buf, &buf, 0);
-                                while (isspace(*buf))
-                                        ++buf;
+                                buf = skip_spaces(buf);
                                 if (*buf == '-') {
-                                        buf += 1;
-                                        while (isspace(*buf))
-                                                ++buf;
+                                        buf = skip_spaces(buf + 1);
                                         end = simple_strtoul(buf, &buf, 0);
                                 } else
                                         end = start;
@@ -373,16 +366,11 @@ static ssize_t pnp_set_current_resources(struct device *dmdev,
                                 continue;
                         }
                         if (!strnicmp(buf, "mem", 3)) {
-                                buf += 3;
-                                while (isspace(*buf))
-                                        ++buf;
+                                buf = skip_spaces(buf + 3);
                                 start = simple_strtoul(buf, &buf, 0);
-                                while (isspace(*buf))
-                                        ++buf;
+                                buf = skip_spaces(buf);
                                 if (*buf == '-') {
-                                        buf += 1;
-                                        while (isspace(*buf))
-                                                ++buf;
+                                        buf = skip_spaces(buf + 1);
                                         end = simple_strtoul(buf, &buf, 0);
                                 } else
                                         end = start;
@@ -390,17 +378,13 @@ static ssize_t pnp_set_current_resources(struct device *dmdev,
                                 continue;
                         }
                         if (!strnicmp(buf, "irq", 3)) {
-                                buf += 3;
-                                while (isspace(*buf))
-                                        ++buf;
+                                buf = skip_spaces(buf + 3);
                                 start = simple_strtoul(buf, &buf, 0);
                                 pnp_add_irq_resource(dev, start, 0);
                                 continue;
                         }
                         if (!strnicmp(buf, "dma", 3)) {
-                                buf += 3;
-                                while (isspace(*buf))
-                                        ++buf;
+                                buf = skip_spaces(buf + 3);
                                 start = simple_strtoul(buf, &buf, 0);
                                 pnp_add_dma_resource(dev, start, 0);
                                 continue;