[PATCH kvm-unit-tests 0/2] Introduce strtoll/strtoull

[PATCH kvm-unit-tests 0/2] Introduce strtoll/strtoull

[Andrew Jones]

A recent posting by Daniele Ahmed inspired me to write a patch adding
strtoll/strtoull. While doing that I noticed check_mul_overflow wasn't
working and found copy+paste errors with it and check_sub_overflow.

Andrew Jones (2):
  compiler.h: Fix typos in mul and sub overflow checks
  lib: Introduce strtoll/strtoull

 lib/linux/compiler.h |  4 ++--
 lib/stdlib.h         |  2 ++
 lib/string.c         | 51 ++++++++++++++++++++++++++++++++------------
 3 files changed, 41 insertions(+), 16 deletions(-)

-- 
2.31.1

[PATCH kvm-unit-tests 1/2] compiler.h: Fix typos in mul and sub overflow checks

[Andrew Jones]

Fixes: 4ceb02bf68f0 ("compiler: Add builtin overflow flag and predicate wrappers")
Signed-off-by: Andrew Jones <drjones@redhat.com>
---
 lib/linux/compiler.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/linux/compiler.h b/lib/linux/compiler.h
index c7fc0cf0852e..6f565e4a5107 100644
--- a/lib/linux/compiler.h
+++ b/lib/linux/compiler.h
@@ -33,8 +33,8 @@
 #elif GCC_VERSION >= 70100
 #define COMPILER_HAS_GENERIC_BUILTIN_OVERFLOW 1
 #define check_add_overflow(a, b) __builtin_add_overflow_p(a, b, (typeof((a) + (b)))0)
-#define check_sub_overflow(a, b) __builtin_add_overflow_p(a, b, (typeof((a) - (b)))0)
-#define check_mul_overflow(a, b) __builtin_add_overflow_p(a, b, (typeof((a) * (b)))0)
+#define check_sub_overflow(a, b) __builtin_sub_overflow_p(a, b, (typeof((a) - (b)))0)
+#define check_mul_overflow(a, b) __builtin_mul_overflow_p(a, b, (typeof((a) * (b)))0)
 #else
 #define check_add_overflow(a, b) ({ (void)((int)(a) == (int)(b)); 0; })
 #define check_sub_overflow(a, b) ({ (void)((int)(a) == (int)(b)); 0; })
-- 
2.31.1

[PATCH kvm-unit-tests 2/2] lib: Introduce strtoll/strtoull

[Andrew Jones]

Signed-off-by: Andrew Jones <drjones@redhat.com>
---
 lib/stdlib.h |  2 ++
 lib/string.c | 51 +++++++++++++++++++++++++++++++++++++--------------
 2 files changed, 39 insertions(+), 14 deletions(-)

diff --git a/lib/stdlib.h b/lib/stdlib.h
index 33c00e8a5204..28496d7ae333 100644
--- a/lib/stdlib.h
+++ b/lib/stdlib.h
@@ -9,5 +9,7 @@
 
 long int strtol(const char *nptr, char **endptr, int base);
 unsigned long int strtoul(const char *nptr, char **endptr, int base);
+long long int strtoll(const char *nptr, char **endptr, int base);
+unsigned long long int strtoull(const char *nptr, char **endptr, int base);
 
 #endif /* _STDLIB_H_ */
diff --git a/lib/string.c b/lib/string.c
index ffc7c7e4f855..27106dae0b0b 100644
--- a/lib/string.c
+++ b/lib/string.c
@@ -168,9 +168,10 @@ static int isspace(int c)
     return c == ' ' || c == '\t' || c == '\r' || c == '\n' || c == '\v' || c == '\f';
 }
 
-static unsigned long __strtol(const char *nptr, char **endptr,
-                              int base, bool is_signed) {
-    unsigned long acc = 0;
+static unsigned long long __strtoll(const char *nptr, char **endptr,
+                                    int base, bool is_signed,
+                                    bool is_longlong) {
+    unsigned long long ull = 0;
     const char *s = nptr;
     int neg, c;
 
@@ -210,36 +211,58 @@ static unsigned long __strtol(const char *nptr, char **endptr,
         else
             break;
 
-        if (is_signed) {
-            long sacc = (long)acc;
-            assert(!check_mul_overflow(sacc, base));
-            assert(!check_add_overflow(sacc * base, c));
+        if (!is_longlong) {
+            if (is_signed) {
+                long sl = (long)ull;
+                assert(!check_mul_overflow(sl, base));
+                assert(!check_add_overflow(sl * base, c));
+            } else {
+                unsigned long ul = (unsigned long)ull;
+                assert(!check_mul_overflow(ul, base));
+                assert(!check_add_overflow(ul * base, c));
+            }
         } else {
-            assert(!check_mul_overflow(acc, base));
-            assert(!check_add_overflow(acc * base, c));
+            if (is_signed) {
+                long long sll = (long long)ull;
+                assert(!check_mul_overflow(sll, base));
+                assert(!check_add_overflow(sll * base, c));
+            } else {
+                assert(!check_mul_overflow(ull, base));
+                assert(!check_add_overflow(ull * base, c));
+            }
         }
 
-        acc = acc * base + c;
+        ull = ull * base + c;
         s++;
     }
 
     if (neg)
-        acc = -acc;
+        ull = -ull;
 
     if (endptr)
         *endptr = (char *)s;
 
-    return acc;
+    return ull;
 }
 
 long int strtol(const char *nptr, char **endptr, int base)
 {
-    return __strtol(nptr, endptr, base, true);
+    return __strtoll(nptr, endptr, base, true, false);
 }
 
 unsigned long int strtoul(const char *nptr, char **endptr, int base)
 {
-    return __strtol(nptr, endptr, base, false);
+    return __strtoll(nptr, endptr, base, false, false);
+}
+
+long long int strtoll(const char *nptr, char **endptr, int base)
+{
+    return __strtoll(nptr, endptr, base, true, true);
+}
+
+unsigned long long int strtoull(const char *nptr, char **endptr, int base)
+{
+    return __strtoll(nptr, endptr, base, false, true);
 }
 
 long atol(const char *ptr)
-- 
2.31.1

Re: [PATCH kvm-unit-tests 2/2] lib: Introduce strtoll/strtoull

[Ahmed, Daniele]

Reviewed-by: Daniele Ahmed <ahmeddan@amazon.com>




Amazon Development Center Germany GmbH
Krausenstr. 38
10117 Berlin
Geschaeftsfuehrung: Christian Schlaeger, Jonathan Weiss
Eingetragen am Amtsgericht Charlottenburg unter HRB 149173 B
Sitz: Berlin
Ust-ID: DE 289 237 879

Re: [PATCH kvm-unit-tests 1/2] compiler.h: Fix typos in mul and sub overflow checks

[Ahmed, Daniele]

Reviewed-by: Daniele Ahmed <ahmeddan@amazon.com>




Amazon Development Center Germany GmbH
Krausenstr. 38
10117 Berlin
Geschaeftsfuehrung: Christian Schlaeger, Jonathan Weiss
Eingetragen am Amtsgericht Charlottenburg unter HRB 149173 B
Sitz: Berlin
Ust-ID: DE 289 237 879

Re: [PATCH kvm-unit-tests 0/2] Introduce strtoll/strtoull

[Paolo Bonzini]

On 13/10/21 18:42, Andrew Jones wrote:
> A recent posting by Daniele Ahmed inspired me to write a patch adding
> strtoll/strtoull. While doing that I noticed check_mul_overflow wasn't
> working and found copy+paste errors with it and check_sub_overflow.
> 
> Andrew Jones (2):
>    compiler.h: Fix typos in mul and sub overflow checks
>    lib: Introduce strtoll/strtoull
> 
>   lib/linux/compiler.h |  4 ++--
>   lib/stdlib.h         |  2 ++
>   lib/string.c         | 51 ++++++++++++++++++++++++++++++++------------
>   3 files changed, 41 insertions(+), 16 deletions(-)
> 

Queued, thanks.

Paolo