small fixes:

fix xstrdup to not grossly overallocate memory
use xopen instean of xopen3 in several places
etc.


git-svn-id: svn://busybox.net/trunk/busybox@16673 69ca8d6d-28ef-0310-b511-8ec308f3f277

1 files changed, 19 insertions, 11 deletions

diff --git a/libbb/xfuncs.c b/libbb/xfuncs.c
index 773e718b8..ade639516 100644
--- a/libbb/xfuncs.c
+++ b/libbb/xfuncs.c
@@ -57,7 +57,7 @@ char * xstrdup(const char *s)
         if (s == NULL)
                 return NULL;
 
-        t = strdup (s);
+        t = strdup(s);
 
         if (t == NULL)
                 bb_error_msg_and_die(bb_msg_memory_exhausted);
@@ -69,23 +69,33 @@ char * xstrdup(const char *s)
 // the (possibly truncated to length n) string into it.
 char * xstrndup(const char *s, int n)
 {
+        int m;
         char *t;
 
         if (ENABLE_DEBUG && s == NULL)
                 bb_error_msg_and_die("xstrndup bug");
 
-        /* TODO: think about xstrndup("abc", 10000)!!! */
-        t = xmalloc(++n);
+        /* We can just xmalloc(n+1) and strncpy into it, */
+        /* but think about xstrndup("abc", 10000) wastage! */
+        m = n;
+        t = (char*) s;
+        while (m) {
+                if (!*t) break;
+                m--; t++;
+        }
+        n = n - m;
+        t = xmalloc(n + 1);
+        t[n] = '\0';
 
-        return safe_strncpy(t,s,n);
+        return memcpy(t,s,n);
 }
 
 // Die if we can't open a file and return a FILE * to it.
 // Notice we haven't got xfread(), This is for use with fscanf() and friends.
 FILE *xfopen(const char *path, const char *mode)
 {
-        FILE *fp;
-        if ((fp = fopen(path, mode)) == NULL)
+        FILE *fp = fopen(path, mode);
+        if (fp == NULL)
                 bb_perror_msg_and_die("%s", path);
         return fp;
 }
@@ -93,8 +103,8 @@ FILE *xfopen(const char *path, const char *mode)
 // Die if we can't open an existing file and return an fd.
 int xopen(const char *pathname, int flags)
 {
-        if (ENABLE_DEBUG && (flags & O_CREAT))
-                bb_error_msg_and_die("xopen() with O_CREAT");
+        //if (ENABLE_DEBUG && (flags & O_CREAT))
+        //      bb_error_msg_and_die("xopen() with O_CREAT");
 
         return xopen3(pathname, flags, 0666);
 }
@@ -142,7 +152,7 @@ off_t xlseek(int fd, off_t offset, int whence)
         return off;
 }
 
-// Die with supplied error message if this FILE * has ferror set.
+// Die with supplied filename if this FILE * has ferror set.
 void die_if_ferror(FILE *fp, const char *fn)
 {
         if (ferror(fp)) {
@@ -214,7 +224,6 @@ void xsetenv(const char *key, const char *value)
                 bb_error_msg_and_die(bb_msg_memory_exhausted);
 }
 
-
 // Converts unsigned long long value into compact 4-char
 // representation. Examples: "1234", "1.2k", " 27M", "123T"
 // Fifth char is always '\0'
@@ -257,7 +266,6 @@ void smart_ulltoa5(unsigned long long ul, char buf[5])
         buf[4] = '\0';
 }
 
-
 // Convert unsigned integer to ascii, writing into supplied buffer.  A
 // truncated result is always null terminated (unless buflen is 0), and
 // contains the first few digits of the result ala strncpy.