In zynq_set_boot_mode() where we parse the string the user has set
the boot-mode option to, we use strncasecmp(str, "qspi", 4) and so
on.  This is wrong, because it means that we will ignore any trailing
junk on the end of the option string, and handle
 -machine boot-mode=sdXYZZY
the same as
 -machine boot-mode=sd

In the documentation we say:
 Supported values are ``jtag``, ``sd``, ``qspi`` and ``nor``.
and that's obviously what we meant to implement.

The correct tool for this job is a simple strcasecmp operation.
Switch to that.

We use the g_ascii_strcasecmp() rather than plain strcasecmp()
because we're comparing ASCII strings here and don't want the
potentially locale-specific behaviour that strcasecmp() implies (and
we're trying to standardize on the glib function for this kind of
string comparison).

Fixes: 7df3747c92d13 ("hw/arm/xilinx_zynq: Add boot-mode property")
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Kostiantyn Kostiuk <kkostiuk@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20260327145012.907264-1-peter.maydell@linaro.org
---
 hw/arm/xilinx_zynq.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/hw/arm/xilinx_zynq.c b/hw/arm/xilinx_zynq.c
index d43f36b718..9dcded9219 100644
--- a/hw/arm/xilinx_zynq.c
+++ b/hw/arm/xilinx_zynq.c
@@ -186,13 +186,13 @@ static void zynq_set_boot_mode(Object *obj, const char *str,
     ZynqMachineState *m = ZYNQ_MACHINE(obj);
     uint8_t mode = 0;
 
-    if (!strncasecmp(str, "qspi", 4)) {
+    if (!g_ascii_strcasecmp(str, "qspi")) {
         mode = 1;
-    } else if (!strncasecmp(str, "sd", 2)) {
+    } else if (!g_ascii_strcasecmp(str, "sd")) {
         mode = 5;
-    } else if (!strncasecmp(str, "nor", 3)) {
+    } else if (!g_ascii_strcasecmp(str, "nor")) {
         mode = 2;
-    } else if (!strncasecmp(str, "jtag", 4)) {
+    } else if (!g_ascii_strcasecmp(str, "jtag")) {
         mode = 0;
     } else {
         error_setg(errp, "%s boot mode not supported", str);
-- 
2.43.0