tools/libs: guest: Use const whenever we point to literal strings

literal strings are not meant to be modified. So we should use const
*char rather than char * when we want to store a pointer to them.

Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Wei Liu <wl@xen.org>

tools/include/xenguest.h

@@ -108,7 +108,7 @@ struct xc_dom_image {
 
     /* info from (elf) kernel image */
     struct elf_dom_parms *parms;
-    char *guest_type;
+    const char *guest_type;
 
     /* memory layout */
     struct xc_dom_seg kernel_seg;
@@ -266,8 +266,8 @@ struct xc_dom_arch {
     /* arch-specific memory initialization. */
     int (*meminit) (struct xc_dom_image * dom);
 
-    char *guest_type;
-    char *native_protocol;
+    const char *guest_type;
+    const char *native_protocol;
     int page_shift;
     int sizeof_pfn;
     int p2m_base_supported;
@@ -374,9 +374,9 @@ char *xc_dom_strdup(struct xc_dom_image *dom, const char *str);
 
 /* --- alloc memory pool ------------------------------------------- */
 
-xen_pfn_t xc_dom_alloc_page(struct xc_dom_image *dom, char *name);
+xen_pfn_t xc_dom_alloc_page(struct xc_dom_image *dom, const char *name);
 int xc_dom_alloc_segment(struct xc_dom_image *dom,
-                         struct xc_dom_seg *seg, char *name,
+                         struct xc_dom_seg *seg, const char *name,
                          xen_vaddr_t start, xen_vaddr_t size);
 
 /* --- misc bits --------------------------------------------------- */

tools/libs/guest/xg_dom_core.c

@@ -422,7 +422,7 @@ void *xc_dom_pfn_to_ptr_retcount(struct xc_dom_image *dom, xen_pfn_t pfn,
     struct xc_dom_phys *phys;
     xen_pfn_t offset;
     unsigned int page_shift = XC_DOM_PAGE_SHIFT(dom);
-    char *mode = "unset";
+    const char *mode = "unset";
 
     *count_out = 0;
 
@@ -525,7 +525,7 @@ void *xc_dom_pfn_to_ptr_retcount(struct xc_dom_image *dom, xen_pfn_t pfn,
     return phys->ptr;
 }
 
-static int xc_dom_chk_alloc_pages(struct xc_dom_image *dom, char *name,
+static int xc_dom_chk_alloc_pages(struct xc_dom_image *dom, const char *name,
                                   xen_pfn_t pages)
 {
     unsigned int page_size = XC_DOM_PAGE_SIZE(dom);
@@ -576,7 +576,7 @@ static int xc_dom_alloc_pad(struct xc_dom_image *dom, xen_vaddr_t boundary)
 }
 
 int xc_dom_alloc_segment(struct xc_dom_image *dom,
-                         struct xc_dom_seg *seg, char *name,
+                         struct xc_dom_seg *seg, const char *name,
                          xen_vaddr_t start, xen_vaddr_t size)
 {
     unsigned int page_size = XC_DOM_PAGE_SIZE(dom);
@@ -611,7 +611,7 @@ int xc_dom_alloc_segment(struct xc_dom_image *dom,
     return 0;
 }
 
-xen_pfn_t xc_dom_alloc_page(struct xc_dom_image *dom, char *name)
+xen_pfn_t xc_dom_alloc_page(struct xc_dom_image *dom, const char *name)
 {
     xen_vaddr_t start;
     xen_pfn_t pfn;

tools/libs/guest/xg_dom_elfloader.c

@@ -50,8 +50,8 @@ void xc_elf_set_logfile(xc_interface *xch, struct elf_binary *elf,
 
 /* ------------------------------------------------------------------------ */
 
-static char *xc_dom_guest_type(struct xc_dom_image *dom,
-                               struct elf_binary *elf)
+static const char *xc_dom_guest_type(struct xc_dom_image *dom,
+                                     struct elf_binary *elf)
 {
     uint64_t machine = elf_uval(elf, elf->ehdr, e_machine);
 

tools/libs/guest/xg_dom_hvmloader.c

@@ -130,7 +130,7 @@ static elf_errorstatus xc_dom_parse_hvm_kernel(struct xc_dom_image *dom)
 
 static int module_init_one(struct xc_dom_image *dom,
                            struct xc_hvm_firmware_module *module,
-                           char *name)
+                           const char *name)
 {
     struct xc_dom_seg seg;
     void *dest;

tools/libs/guest/xg_dom_x86.c

@@ -1148,10 +1148,11 @@ static int vcpu_hvm(struct xc_dom_image *dom)
 
 /* ------------------------------------------------------------------------ */
 
-static int x86_compat(xc_interface *xch, uint32_t domid, char *guest_type)
+static int x86_compat(xc_interface *xch, uint32_t domid,
+                      const char *guest_type)
 {
     static const struct {
-        char           *guest;
+        const char      *guest;
         uint32_t        size;
     } types[] = {
         { "xen-3.0-x86_32p", 32 },
@@ -1664,7 +1665,7 @@ static int bootearly(struct xc_dom_image *dom)
 static int bootlate_pv(struct xc_dom_image *dom)
 {
     static const struct {
-        char *guest;
+        const char *guest;
         unsigned long pgd_type;
     } types[] = {
         { "xen-3.0-x86_32",  MMUEXT_PIN_L2_TABLE},

tools/libs/guest/xg_private.h

@@ -43,7 +43,7 @@
 #endif
 
 struct xc_dom_loader {
-    char *name;
+    const char *name;
     /* Sadly the error returns from these functions are not consistent: */
     elf_negerrnoval (*probe) (struct xc_dom_image * dom);
     elf_negerrnoval (*parser) (struct xc_dom_image * dom);