diff: failed to confirm "static bug" in gcc - reinstating statics.

microscopic code improvements.


git-svn-id: svn://busybox.net/trunk/busybox@18051 69ca8d6d-28ef-0310-b511-8ec308f3f277

3 files changed, 81 insertions, 78 deletions

diff --git a/coreutils/chgrp.c b/coreutils/chgrp.c
index eaa29cbc6..cfb8c15b2 100644
--- a/coreutils/chgrp.c
+++ b/coreutils/chgrp.c
@@ -7,15 +7,12 @@
  * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
  */
 
-/* BB_AUDIT SUSv3 defects - unsupported options -H, -L, and -P. */
+/* BB_AUDIT SUSv3 defects - none? */
 /* BB_AUDIT GNU defects - unsupported long options. */
 /* http://www.opengroup.org/onlinepubs/007904975/utilities/chgrp.html */
 
 #include "busybox.h"
 
-/* FIXME - move to .h */
-extern int chown_main(int argc, char **argv);
-
 int chgrp_main(int argc, char **argv);
 int chgrp_main(int argc, char **argv)
 {
diff --git a/coreutils/diff.c b/coreutils/diff.c
index 0eaf0b1d1..73b576f31 100644
--- a/coreutils/diff.c
+++ b/coreutils/diff.c
@@ -65,18 +65,25 @@
 #define FLAG_U  (1<<12)
 #define FLAG_w  (1<<13)
 
-/* XXX: FIXME: the following variables should be static, but gcc currently
+/* The following variables should be static, but gcc currently
  * creates a much bigger object if we do this. [which version of gcc? --vda] */
 /* 4.x, IIRC also 3.x --bernhard */
+/* Works for gcc 3.4.3. Sizes without and with "static":
+   # size busybox.t[34]/coreutils/diff.o
+   text    data     bss     dec     hex filename
+   6969       8     305    7282    1c72 busybox.t3/coreutils/diff.o
+   6969       8     305    7282    1c72 busybox.t4/coreutils/diff.o
+   --vda
+ */
 /* This is the default number of lines of context. */
-int context = 3;
-int status;
-char *start;
-const char *label1;
-const char *label2;
-struct stat stb1, stb2;
-char **dl;
-USE_FEATURE_DIFF_DIR(int dl_count;)
+static int context = 3;
+static int status;
+static char *start;
+static const char *label1;
+static const char *label2;
+static struct stat stb1, stb2;
+static char **dl;
+USE_FEATURE_DIFF_DIR(static int dl_count;)
 
 struct cand {
         int x;
@@ -84,7 +91,7 @@ struct cand {
         int pred;
 };
 
-struct line {
+static struct line {
         int serial;
         int value;
 } *file[2];
@@ -188,7 +195,7 @@ static int readhash(FILE * f)
 
         sum = 1;
         space = 0;
-        if (!(option_mask32 & FLAG_b) && !(option_mask32 & FLAG_w)) {
+        if (!(option_mask32 & (FLAG_b | FLAG_w))) {
                 for (i = 0; (t = getc(f)) != '\n'; i++) {
                         if (t == EOF) {
                                 if (i == 0)
@@ -241,19 +248,18 @@ static int files_differ(FILE * f1, FILE * f2, int flags)
 {
         size_t i, j;
 
-        if ((flags & (D_EMPTY1 | D_EMPTY2)) || stb1.st_size != stb2.st_size ||
-                (stb1.st_mode & S_IFMT) != (stb2.st_mode & S_IFMT))
+        if ((flags & (D_EMPTY1 | D_EMPTY2)) || stb1.st_size != stb2.st_size
+         || (stb1.st_mode & S_IFMT) != (stb2.st_mode & S_IFMT)
+        ) {
                 return 1;
+        }
         while (1) {
                 i = fread(bb_common_bufsiz1,            1, BUFSIZ/2, f1);
                 j = fread(bb_common_bufsiz1 + BUFSIZ/2, 1, BUFSIZ/2, f2);
                 if (i != j)
                         return 1;
-                if (i == 0 && j == 0) {
-                        if (ferror(f1) || ferror(f2))
-                                return 1;
-                        return 0;
-                }
+                if (i == 0)
+                        return (ferror(f1) || ferror(f2));
                 if (memcmp(bb_common_bufsiz1,
                            bb_common_bufsiz1 + BUFSIZ/2, i) != 0)
                         return 1;
@@ -337,11 +343,11 @@ static void equiv(struct line *a, int n, struct line *b, int m, int *c)
 
 static int isqrt(int n)
 {
-        int y, x = 1;
+        int y, x;
 
         if (n == 0)
                 return 0;
-
+        x = 1;
         do {
                 y = x;
                 x = n / x;
@@ -647,7 +653,6 @@ static void fetch(long *f, int a, int b, FILE * lb, int ch)
                         }
                 }
         }
-        return;
 }
 
 
@@ -828,66 +833,66 @@ static void output(char *file1, FILE * f1, char *file2, FILE * f2)
 }
 
 /*
- *      The following code uses an algorithm due to Harold Stone,
- *      which finds a pair of longest identical subsequences in
- *      the two files.
+ * The following code uses an algorithm due to Harold Stone,
+ * which finds a pair of longest identical subsequences in
+ * the two files.
  *
- *      The major goal is to generate the match vector J.
- *      J[i] is the index of the line in file1 corresponding
- *      to line i file0. J[i] = 0 if there is no
- *      such line in file1.
+ * The major goal is to generate the match vector J.
+ * J[i] is the index of the line in file1 corresponding
+ * to line i file0. J[i] = 0 if there is no
+ * such line in file1.
  *
- *      Lines are hashed so as to work in core. All potential
- *      matches are located by sorting the lines of each file
- *      on the hash (called ``value''). In particular, this
- *      collects the equivalence classes in file1 together.
- *      Subroutine equiv replaces the value of each line in
- *      file0 by the index of the first element of its
- *      matching equivalence in (the reordered) file1.
- *      To save space equiv squeezes file1 into a single
- *      array member in which the equivalence classes
- *      are simply concatenated, except that their first
- *      members are flagged by changing sign.
+ * Lines are hashed so as to work in core. All potential
+ * matches are located by sorting the lines of each file
+ * on the hash (called ``value''). In particular, this
+ * collects the equivalence classes in file1 together.
+ * Subroutine equiv replaces the value of each line in
+ * file0 by the index of the first element of its
+ * matching equivalence in (the reordered) file1.
+ * To save space equiv squeezes file1 into a single
+ * array member in which the equivalence classes
+ * are simply concatenated, except that their first
+ * members are flagged by changing sign.
  *
- *      Next the indices that point into member are unsorted into
- *      array class according to the original order of file0.
+ * Next the indices that point into member are unsorted into
+ * array class according to the original order of file0.
  *
- *      The cleverness lies in routine stone. This marches
- *      through the lines of file0, developing a vector klist
- *      of "k-candidates". At step i a k-candidate is a matched
- *      pair of lines x,y (x in file0 y in file1) such that
- *      there is a common subsequence of length k
- *      between the first i lines of file0 and the first y
- *      lines of file1, but there is no such subsequence for
- *      any smaller y. x is the earliest possible mate to y
- *      that occurs in such a subsequence.
+ * The cleverness lies in routine stone. This marches
+ * through the lines of file0, developing a vector klist
+ * of "k-candidates". At step i a k-candidate is a matched
+ * pair of lines x,y (x in file0 y in file1) such that
+ * there is a common subsequence of length k
+ * between the first i lines of file0 and the first y
+ * lines of file1, but there is no such subsequence for
+ * any smaller y. x is the earliest possible mate to y
+ * that occurs in such a subsequence.
  *
- *      Whenever any of the members of the equivalence class of
- *      lines in file1 matable to a line in file0 has serial number
- *      less than the y of some k-candidate, that k-candidate
- *      with the smallest such y is replaced. The new
- *      k-candidate is chained (via pred) to the current
- *      k-1 candidate so that the actual subsequence can
- *      be recovered. When a member has serial number greater
- *      that the y of all k-candidates, the klist is extended.
- *      At the end, the longest subsequence is pulled out
- *      and placed in the array J by unravel
+ * Whenever any of the members of the equivalence class of
+ * lines in file1 matable to a line in file0 has serial number
+ * less than the y of some k-candidate, that k-candidate
+ * with the smallest such y is replaced. The new
+ * k-candidate is chained (via pred) to the current
+ * k-1 candidate so that the actual subsequence can
+ * be recovered. When a member has serial number greater
+ * that the y of all k-candidates, the klist is extended.
+ * At the end, the longest subsequence is pulled out
+ * and placed in the array J by unravel
  *
- *      With J in hand, the matches there recorded are
- *      checked against reality to assure that no spurious
- *      matches have crept in due to hashing. If they have,
- *      they are broken, and "jackpot" is recorded--a harmless
- *      matter except that a true match for a spuriously
- *      mated line may now be unnecessarily reported as a change.
+ * With J in hand, the matches there recorded are
+ * checked against reality to assure that no spurious
+ * matches have crept in due to hashing. If they have,
+ * they are broken, and "jackpot" is recorded--a harmless
+ * matter except that a true match for a spuriously
+ * mated line may now be unnecessarily reported as a change.
  *
- *      Much of the complexity of the program comes simply
- *      from trying to minimize core utilization and
- *      maximize the range of doable problems by dynamically
- *      allocating what is needed and reusing what is not.
- *      The core requirements for problems larger than somewhat
- *      are (in words) 2*length(file0) + length(file1) +
- *      3*(number of k-candidates installed),  typically about
- *      6n words for files of length n.
+ * Much of the complexity of the program comes simply
+ * from trying to minimize core utilization and
+ * maximize the range of doable problems by dynamically
+ * allocating what is needed and reusing what is not.
+ * The core requirements for problems larger than somewhat
+ * are (in words) 2*length(file0) + length(file1) +
+ * 3*(number of k-candidates installed),  typically about
+ * 6n words for files of length n.
  */
 static unsigned diffreg(char * ofile1, char * ofile2, int flags)
 {
diff --git a/include/libbb.h b/include/libbb.h
index 9aa060691..93edbdc3f 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -514,6 +514,7 @@ int bb_test(int argc, char** argv);
 #if ENABLE_ROUTE
 void bb_displayroutes(int noresolve, int netstatfmt);
 #endif
+int chown_main(int argc, char **argv);
 #if ENABLE_GUNZIP
 int gunzip_main(int argc, char **argv);
 #endif