Make sure that argv[] argument pointers are not modified.

The hush shell dynamically allocates (and re-allocates) memory for the
argument strings in the "char *argv[]" argument vector passed to
commands.  Any code that modifies these pointers will cause serious
corruption of the malloc data structures and crash U-Boot, so make
sure the compiler can check that no such modifications are being done
by changing the code into "char * const argv[]".

This modification is the result of debugging a strange crash caused
after adding a new command, which used the following argument
processing code which has been working perfectly fine in all Unix
systems since version 6 - but not so in U-Boot:

int main (int argc, char **argv)
{
	while (--argc > 0 && **++argv == '-') {
/* ====> */	while (*++*argv) {
			switch (**argv) {
			case 'd':
				debug++;
				break;
			...
			default:
				usage ();
			}
		}
	}
	...
}

The line marked "====>" will corrupt the malloc data structures and
usually cause U-Boot to crash when the next command gets executed by
the shell.  With the modification, the compiler will prevent this with
an
	error: increment of read-only location '*argv'

N.B.: The code above can be trivially rewritten like this:

	while (--argc > 0 && **++argv == '-') {
		char *arg = *argv;
		while (*++arg) {
			switch (*arg) {
			...

Signed-off-by: Wolfgang Denk <wd@denx.de>
Acked-by: Mike Frysinger <vapier@gentoo.org>

11 files changed, 12 insertions, 12 deletions

diff --git a/examples/standalone/82559_eeprom.c b/examples/standalone/82559_eeprom.c
index 5e2eee9..8dd7079 100644
--- a/examples/standalone/82559_eeprom.c
+++ b/examples/standalone/82559_eeprom.c
@@ -305,7 +305,7 @@ write_config_word(int bus, int dev, int func, int reg, u16 data)
 }
 
 
-int main (int argc, char *argv[])
+int main (int argc, char * const argv[])
 {
 	unsigned char *eth_addr;
 	uchar buf[6];
diff --git a/examples/standalone/atmel_df_pow2.c b/examples/standalone/atmel_df_pow2.c
index db0cd69..b5b4503 100644
--- a/examples/standalone/atmel_df_pow2.c
+++ b/examples/standalone/atmel_df_pow2.c
@@ -114,7 +114,7 @@ static char *getline(void)
 	}
 }
 
-int atmel_df_pow2(int argc, char *argv[])
+int atmel_df_pow2(int argc, char * const argv[])
 {
 	/* Print the ABI version */
 	app_startup(argv);
diff --git a/examples/standalone/eepro100_eeprom.c b/examples/standalone/eepro100_eeprom.c
index 771a7e8..3c7f380 100644
--- a/examples/standalone/eepro100_eeprom.c
+++ b/examples/standalone/eepro100_eeprom.c
@@ -25,7 +25,7 @@
 
 static int reset_eeprom(unsigned long ioaddr, unsigned char *hwaddr);
 
-int eepro100_eeprom(int argc, char *argv[])
+int eepro100_eeprom(int argc, char * const argv[])
 {
 	int ret = 0;
 
diff --git a/examples/standalone/hello_world.c b/examples/standalone/hello_world.c
index 9317f6d..067c390 100644
--- a/examples/standalone/hello_world.c
+++ b/examples/standalone/hello_world.c
@@ -24,7 +24,7 @@
 #include <common.h>
 #include <exports.h>
 
-int hello_world (int argc, char *argv[])
+int hello_world (int argc, char * const argv[])
 {
 	int i;
 
diff --git a/examples/standalone/interrupt.c b/examples/standalone/interrupt.c
index f3061d1..a5b58a1 100644
--- a/examples/standalone/interrupt.c
+++ b/examples/standalone/interrupt.c
@@ -44,7 +44,7 @@
 
 static void irq_handler (void *arg);
 
-int interrupt (int argc, char *argv[])
+int interrupt (int argc, char * const argv[])
 {
 	int c, irq = -1;
 
diff --git a/examples/standalone/mem_to_mem_idma2intr.c b/examples/standalone/mem_to_mem_idma2intr.c
index f35f1ba..d0a75ea 100644
--- a/examples/standalone/mem_to_mem_idma2intr.c
+++ b/examples/standalone/mem_to_mem_idma2intr.c
@@ -204,9 +204,9 @@ int memcmp(const void * cs,const void * ct,size_t count)
 #endif	/* STANDALONE */
 
 #ifdef STANDALONE
-int mem_to_mem_idma2intr (int argc, char *argv[])
+int mem_to_mem_idma2intr (int argc, char * const argv[])
 #else
-int do_idma (bd_t * bd, int argc, char *argv[])
+int do_idma (bd_t * bd, int argc, char * const argv[])
 #endif	/* STANDALONE */
 {
 	int i;
diff --git a/examples/standalone/smc91111_eeprom.c b/examples/standalone/smc91111_eeprom.c
index b91f34c..c98b0fc 100644
--- a/examples/standalone/smc91111_eeprom.c
+++ b/examples/standalone/smc91111_eeprom.c
@@ -48,7 +48,7 @@ void print_MAC (struct eth_device *dev);
 int read_eeprom_reg (struct eth_device *dev, int reg);
 void print_macaddr (struct eth_device *dev);
 
-int smc91111_eeprom (int argc, char *argv[])
+int smc91111_eeprom (int argc, char * const argv[])
 {
 	int c, i, j, done, line, reg, value, start, what;
 	char input[50];
diff --git a/examples/standalone/smc911x_eeprom.c b/examples/standalone/smc911x_eeprom.c
index 104047f..c51a050 100644
--- a/examples/standalone/smc911x_eeprom.c
+++ b/examples/standalone/smc911x_eeprom.c
@@ -313,7 +313,7 @@ static char *getline(void)
 /**
  *	smc911x_eeprom - our application's main() function
  */
-int smc911x_eeprom(int argc, char *argv[])
+int smc911x_eeprom(int argc, char * const argv[])
 {
 	/* Avoid initializing on stack as gcc likes to call memset() */
 	struct eth_device dev;
diff --git a/examples/standalone/stubs.c b/examples/standalone/stubs.c
index f3e1ab5..2d2e709 100644
--- a/examples/standalone/stubs.c
+++ b/examples/standalone/stubs.c
@@ -189,7 +189,7 @@ void __attribute__((unused)) dummy(void)
 
 extern unsigned long __bss_start, _end;
 
-void app_startup(char **argv)
+void app_startup(char * const *argv)
 {
 	unsigned char * cp = (unsigned char *) &__bss_start;
 
diff --git a/examples/standalone/test_burst.c b/examples/standalone/test_burst.c
index 7109c09..2b101b7 100644
--- a/examples/standalone/test_burst.c
+++ b/examples/standalone/test_burst.c
@@ -85,7 +85,7 @@ static unsigned long test_pattern [] = {
 };
 
 
-int test_burst (int argc, char *argv[])
+int test_burst (int argc, char * const argv[])
 {
 	unsigned long size = CACHE_LINE_SIZE;
 	unsigned int pass = 0;
diff --git a/examples/standalone/timer.c b/examples/standalone/timer.c
index 6628b21..834cc9a 100644
--- a/examples/standalone/timer.c
+++ b/examples/standalone/timer.c
@@ -115,7 +115,7 @@ void setPeriod (tid_8xx_cpmtimer_t *hwp, ulong interval);
 
 static char *usage = "\n[q, b, e, ?] ";
 
-int timer (int argc, char *argv[])
+int timer (int argc, char * const argv[])
 {
 	cpmtimer8xx_t *cpmtimerp;	/* Pointer to the CPM Timer structure   */
 	tid_8xx_cpmtimer_t hw;