allocate only as many FILE's as needed

SCCS-vsn: lib/libc/stdio/findfp.c 1.3

diff --git a/usr/src/lib/libc/stdio/findfp.c b/usr/src/lib/libc/stdio/findfp.c
index c8f74ea..cbcf288 100644 (file)
--- a/usr/src/lib/libc/stdio/findfp.c
+++ b/usr/src/lib/libc/stdio/findfp.c
@@ -1,92 +1,79 @@
-/* @(#)findfp.c        1.2 (Berkeley) %G% */
+/* @(#)findfp.c        1.3 (Berkeley) %G% */

 #include <stdio.h>
 
 #include <stdio.h>
 

-#define NSTATIC        10      /* stdin, stdout, stderr, plus slack */
+#define active(iop)    ((iop)->_flag & (_IOREAD|_IOWRT|_IORW))

 
 

-extern char *calloc();
-
-static FILE *dummy[NSTATIC];
-static FILE **iov = NULL;
-static FILE **iovend;
+#define NSTATIC        3       /* stdin + stdout + stderr */

 
 FILE _iob[NSTATIC] = {
 
 FILE _iob[NSTATIC] = {

-       { 0, NULL, NULL, NULL, _IOREAD,         0 },    /* stdin  */
-       { 0, NULL, NULL, NULL, _IOWRT,          1 },    /* stdout */
-       { 0, NULL, NULL, NULL, _IOWRT|_IONBF,   2 },    /* stderr */
+       { 0, NULL, NULL, 0, _IOREAD,            0 },    /* stdin  */
+       { 0, NULL, NULL, 0, _IOWRT,             1 },    /* stdout */
+       { 0, NULL, NULL, 0, _IOWRT|_IONBF,      2 },    /* stderr */

 };
 
 };
 

-static char smallbuf[NSTATIC];
-static char *unbufp = NULL;
+static FILE    *_lastbuf = _iob + NSTATIC;
+
+extern char    *calloc();
+
+static FILE    **iobglue;
+static FILE    **endglue;
+static int     nfiles;

 
 FILE *
 _findiop()
 {
 
 FILE *
 _findiop()
 {

-       register FILE **iovp;
+       register FILE **iov;

        register FILE *fp;
        register FILE *fp;

-       register int nfiles;
-
-       if (iov == NULL) {
-               unbufp  = NULL;
-               iov     = NULL;
-               fp      = NULL;

 
 

+       if (nfiles <= 0)

                nfiles = getdtablesize();
                nfiles = getdtablesize();

-               if (nfiles > NSTATIC) {
-                       fp = (FILE *)calloc(nfiles - NSTATIC, sizeof *fp);
-                       if (fp != NULL) {
-                               iov = (FILE **)calloc(nfiles, sizeof *iov);
-                               if (iov != NULL)
-                                       unbufp = calloc(nfiles, sizeof *unbufp);
-                       }
-               }
-
-               if (unbufp != NULL) {
-                       iovend = iov + nfiles;
-                       for (iovp = iov + NSTATIC; iovp < iovend; /* void */)
-                               *iovp++ = fp++;
-               } else {
-                       if (fp != NULL) {
-                               free((char *)fp);
-                               if (iov != NULL)
-                                       free((char *)iov);
-                       }
-
-                       iovend  = dummy + NSTATIC;
-                       iov     = dummy;
-               }
-
-               iovp = iov;
-               for (fp = _iob; fp < _iob + NSTATIC; /* void */)
-                       *iovp++ = fp++;
+
+       if (iobglue == NULL) {
+               iobglue = (FILE **)calloc(nfiles, sizeof *iobglue);
+               if (iobglue == NULL)
+                       return (NULL);
+
+               endglue = iobglue + nfiles;
+
+               iov = iobglue;
+               for (fp = _iob; fp < _lastbuf; /* void */)
+                       *iov++ = fp++;

        }
 
        }
 

-       for (iovp = iov; (*iovp)->_flag & (_IOREAD|_IOWRT|_IORW); /* void */)
-               if (++iovp >= iovend)
+       iov = iobglue;
+       while (*iov != NULL && active(*iov))
+               if (++iov >= endglue)

                        return (NULL);
 
                        return (NULL);
 

-       return (*iovp);
+       if (*iov == NULL)
+               *iov = (FILE *)calloc(1, sizeof **iov);
+
+       return (*iov);

 }
 
 }
 

-_cleanup()
+_fwalk(function)
+       register int (*function)();

 {
 {

-       register FILE *_lastbuf = _iob + NSTATIC;
-       register FILE **iovp;
-       register FILE *iop;
-
-       if (iov == NULL)
-               for (iop = _iob; iop < _lastbuf; iop++)
-                       fclose(iop);
-       else
-               for (iovp = iov; iovp < iovend; iovp++)
-                       fclose(*iovp);
+       register FILE **iov;
+       register FILE *fp;
+
+       if (function == NULL)
+               return;
+
+       if (iobglue == NULL) {
+               for (fp = _iob; fp < _lastbuf; fp++)
+                       if (active(fp))
+                               (*function)(fp);
+       } else {
+               for (iov = iobglue; iov < endglue; iov++)
+                       if (*iov != NULL && active(*iov))
+                               (*function)(*iov);
+       }

 }
 
 }
 

-char *
-_smallbuf(iop)
-       register FILE *iop;
+_cleanup()

 {
 {

-       if (unbufp == NULL)
-               return (&smallbuf[iop - _iob]);
-       else
-               return (&unbufp[fileno(iop)]);
+       extern int fclose();
+
+       _fwalk(fclose);

 }
 }