First commit

Signed-off-by: Mattias Andrée <maandree@kth.se>

1 files changed, 54 insertions, 0 deletions

diff --git a/linux/types.c b/linux/types.c
new file mode 100644
index 0000000..fee69fe
--- /dev/null
+++ b/linux/types.c
@@ -0,0 +1,54 @@
+/* See LICENSE file for copyright and license details. */
+
+/* This file is included from ../libsyscalls_get_datatype_description.c */
+
+
+/* If new architectures are added, the table at the top of
+ * ../libsyscalls_get_datatype_description.c must be updated */
+
+
+static enum libsyscalls_error
+get_linux_datatype_description(enum libsyscalls_arch arch, enum libsyscalls_datatype *datatype,
+                               struct libsyscalls_datatype_description *description_out,
+			       int *divide_array_size_with_type_size_out)
+{
+	/*
+	 * Generally Linux has char as 8 bit, short int as 16, int as 32 bit,
+	 * and long long int as 64 bit (it's code even make such assumptions),
+	 * however that's is not necessarily the case for more exotic
+	 * architectures, for example, some specialised processors have 16 bit
+	 * chars and run Linux (although not mainline). Linux also used
+	 * long int for addresses (intptr_t), which is normally how it should
+	 * be done but Windows always set long int to 32 bit (at least on x86/amd64)
+	 * for backwards compatibility, and of course it cannot be assumed that
+	 * Linux does something similar this for some architecture in the future
+	 * (although that looks very unlikely, at least 32+-bit architecture,
+	 * it is of course possible that if Linux is ported to a 16-bit architecture,
+	 * intptr_t would be 16 bits, and thus long int must be something else
+	 * as it must be at least 32 bits). It's probably safe to assume,
+	 * system calls use intptr_t/uintptr_t.
+	 */
+
+	switch ((int)*datatype) {
+	case LIBSYSCALLS_TYPE_SCHAR:  description_out->width_in_bits = 8;  break;
+	case LIBSYSCALLS_TYPE_SHORT:  description_out->width_in_bits = 16; break;
+	case LIBSYSCALLS_TYPE_INT:    description_out->width_in_bits = 32; break;
+	case LIBSYSCALLS_TYPE_LLONG:  description_out->width_in_bits = 64; break;
+
+	case LIBSYSCALLS_TYPE_LONG:
+	case LIBSYSCALLS_TYPE_DYNAMIC: /* syscall */
+		*datatype = LIBSYSCALLS_TYPE_INTPTR;
+		break;
+
+	case LIBSYSCALLS_TYPE_FD_SET:
+		*datatype = LIBSYSCALLS_TYPE_INTPTR;
+		description_out->array_size = 1024;
+		*divide_array_size_with_type_size_out = 1;
+		break;
+
+	default:
+		/* something only defined on some other operating system */
+		return LIBSYSCALLS_E_NOSUCHTYPE;
+	}
+	return LIBSYSCALLS_E_OK;
+}