Cleanup ARM ioperm implementation (step 2)

Since GLIBC requires a minimum 2.6.32 kernel, the sysctl (CTL_BUS,
CTL_BUS_ISA, ISA_*) is always available.  We can therefore remove the
fallback code reading /etc/arm_systype or parsing /proc/cpuinfo.

Remove fscanf from localplt.data as it is no longer called from within
GLIBC.

	* sysdeps/unix/sysv/linux/arm/ioperm.c: Do not include <string.h>.
	(PATH_ARM_SYSTYPE): Remove.
	(PATH_CPUINFO): Likewise.
	(IO_BASE_FOOTBRIDGE): Likewise.
	(IO_SHIFT_FOOTBRIDGE): Likewise.
	(struct platform): Likewise.
	(init_iosys): Remove compatibility code for 2.4 kernels.
	* sysdeps/unix/sysv/linux/arm/localplt.data: Remove fscanf.

ChangeLog

@@ -1,3 +1,14 @@
+2015-12-30  Aurelien Jarno  <aurelien@aurel32.net>
+
+	* sysdeps/unix/sysv/linux/arm/ioperm.c: Do not include <string.h>.
+	(PATH_ARM_SYSTYPE): Remove.
+	(PATH_CPUINFO): Likewise.
+	(IO_BASE_FOOTBRIDGE): Likewise.
+	(IO_SHIFT_FOOTBRIDGE): Likewise.
+	(struct platform): Likewise.
+	(init_iosys): Remove compatibility code for 2.4 kernels.
+	* sysdeps/unix/sysv/linux/arm/localplt.data: Remove fscanf.
+
 2015-12-29  Florian Weimer  <fweimer@redhat.com>
 
 	* malloc/tst-malloc-thread-fail.c: New file.

sysdeps/unix/sysv/linux/arm/ioperm.c

@@ -37,17 +37,13 @@
 #include <stdio.h>
 #include <ctype.h>
 #include <stdlib.h>
-#include <string.h>
 #include <unistd.h>
 
 #include <sys/types.h>
 #include <sys/mman.h>
 
 #include <sys/sysctl.h>
 
-#define PATH_ARM_SYSTYPE	"/etc/arm_systype"
-#define PATH_CPUINFO		"/proc/cpuinfo"
-
 #define MAX_PORT	0x10000
 
 static struct {
@@ -57,47 +53,16 @@ static struct {
   unsigned int		initdone;	/* since all the above could be 0 */
 } io;
 
-#define IO_BASE_FOOTBRIDGE	0x7c000000
-#define IO_SHIFT_FOOTBRIDGE	0
-
-static struct platform {
-  const char		*name;
-  unsigned long int	io_base;
-  unsigned int		shift;
-} platform[] = {
-  /* All currently supported platforms are in fact the same. :-)  */
-  {"Chalice-CATS",	IO_BASE_FOOTBRIDGE,	IO_SHIFT_FOOTBRIDGE},
-  {"DEC-EBSA285",	IO_BASE_FOOTBRIDGE,	IO_SHIFT_FOOTBRIDGE},
-  {"Corel-NetWinder",	IO_BASE_FOOTBRIDGE,	IO_SHIFT_FOOTBRIDGE},
-  {"Rebel-NetWinder",	IO_BASE_FOOTBRIDGE,	IO_SHIFT_FOOTBRIDGE},
-};
-
 #define IO_ADDR(port)	(io.base + ((port) << io.shift))
 
 /*
- * Initialize I/O system.  There are several ways to get the information
- * we need.  Each is tried in turn until one succeeds.
- *
- * 1. Sysctl (CTL_BUS, CTL_BUS_ISA, ISA_*).  This is the preferred method
- *    but not all kernels support it.
- *
- * 2. Read the value (not the contents) of symlink PATH_ARM_SYSTYPE.
- *    - If it matches one of the entries in the table above, use the
- *      corresponding values.
- *    - If it begins with a number, assume this is a previously
- *      unsupported system and the values encode, in order,
- *      "<io_base>,<port_shift>".
- *
- * 3. Lookup the "system type" field in /proc/cpuinfo.  Again, if it
- *    matches an entry in the platform[] table, use the corresponding
- *    values.
+ * Initialize I/O system.  The io_bae and port_shift values are fetched
+ * using sysctl (CTL_BUS, CTL_BUS_ISA, ISA_*).
  */
 
 static int
 init_iosys (void)
 {
-  char systype[256];
-  int i, n;
   static int iobase_name[] = { CTL_BUS, CTL_BUS_ISA, BUS_ISA_PORT_BASE };
   static int ioshift_name[] = { CTL_BUS, CTL_BUS_ISA, BUS_ISA_PORT_SHIFT };
   size_t len = sizeof(io.base);
@@ -109,61 +74,7 @@ init_iosys (void)
       return 0;
     }
 
-  n = __readlink (PATH_ARM_SYSTYPE, systype, sizeof (systype) - 1);
-  if (n > 0)
-    {
-      systype[n] = '\0';
-      if (isdigit (systype[0]))
-	{
-	  if (sscanf (systype, "%li,%i", &io.io_base, &io.shift) == 2)
-	    {
-	      io.initdone = 1;
-	      return 0;
-	    }
-	  /* else we're likely going to fail with the system match below */
-	}
-    }
-  else
-    {
-      FILE * fp;
-
-      fp = fopen (PATH_CPUINFO, "rce");
-      if (! fp)
-	return -1;
-      while ((n = fscanf (fp, "Hardware\t: %256[^\n]\n", systype))
-	     != EOF)
-	{
-	  if (n == 1)
-	    break;
-	  else
-	    fgets_unlocked (systype, 256, fp);
-	}
-      fclose (fp);
-
-      if (n == EOF)
-	{
-	  /* this can happen if the format of /proc/cpuinfo changes...  */
-	  fprintf (stderr,
-		   "ioperm: Unable to determine system type.\n"
-		   "\t(May need " PATH_ARM_SYSTYPE " symlink?)\n");
-	  __set_errno (ENODEV);
-	  return -1;
-	}
-    }
-
-  /* translate systype name into i/o system: */
-  for (i = 0; i < sizeof (platform) / sizeof (platform[0]); ++i)
-    {
-      if (strcmp (platform[i].name, systype) == 0)
-	{
-	  io.shift = platform[i].shift;
-	  io.io_base = platform[i].io_base;
-	  io.initdone = 1;
-	  return 0;
-	}
-    }
-
-  /* systype is not a known platform name... */
+  /* sysctl has failed... */
   __set_errno (ENODEV);
   return -1;
 }

sysdeps/unix/sysv/linux/arm/localplt.data

@@ -1,6 +1,5 @@
 libc.so: calloc
 libc.so: free
-libc.so: fscanf
 libc.so: malloc
 libc.so: memalign
 libc.so: raise