tf_printf: Return number of printed characters

The C standard says that printf() has to return the number of characters
it has printed.

Change-Id: I0ef50b1d6766d140724ac0a2fa2c5d023431f984
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

diff --git a/common/tf_printf.c b/common/tf_printf.c
index 9d8333a6b0811dde334e188e8830c557524bb3fe..ecf058ca9b8c3f67ade4877fa46574737807fa69 100644 (file)
--- a/common/tf_printf.c
+++ b/common/tf_printf.c
@@ -23,20 +23,26 @@
        (((_lcount) > 1) ? va_arg(_args, unsigned long long int) :      \
        ((_lcount) ? va_arg(_args, unsigned long int) : va_arg(_args, unsigned int)))
 
-void tf_string_print(const char *str)
+int tf_string_print(const char *str)
 {
+       int count = 0;
+
        assert(str);
 
-       while (*str)
+       while (*str) {
                putchar(*str++);
+               count++;
+       }
+
+       return count;
 }
 
-static void unsigned_num_print(unsigned long long int unum, unsigned int radix,
-                              char padc, int padn)
+static int unsigned_num_print(unsigned long long int unum, unsigned int radix,
+                             char padc, int padn)
 {
        /* Just need enough space to store 64 bit decimal integer */
        unsigned char num_buf[20];
-       int i = 0, rem;
+       int i = 0, rem, count = 0;
 
        do {
                rem = unum % radix;
@@ -49,11 +55,16 @@ static void unsigned_num_print(unsigned long long int unum, unsigned int radix,
        if (padn > 0) {
                while (i < padn--) {
                        putchar(padc);
+                       count++;
                }
        }
 
-       while (--i >= 0)
+       while (--i >= 0) {
                putchar(num_buf[i]);
+               count++;
+       }
+
+       return count;
 }
 
 /*******************************************************************
@@ -76,7 +87,7 @@ static void unsigned_num_print(unsigned long long int unum, unsigned int radix,
  * The print exits on all other formats specifiers other than valid
  * combinations of the above specifiers.
  *******************************************************************/
-void tf_vprintf(const char *fmt, va_list args)
+int tf_vprintf(const char *fmt, va_list args)
 {
        int l_count;
        long long int num;
@@ -84,6 +95,7 @@ void tf_vprintf(const char *fmt, va_list args)
        char *str;
        char padc = 0; /* Padding character */
        int padn; /* Number of characters to pad */
+       int count = 0; /* Number of printed characters */
 
        while (*fmt) {
                l_count = 0;
@@ -104,24 +116,27 @@ loop:
                                } else
                                        unum = (unsigned long long int)num;
 
-                               unsigned_num_print(unum, 10, padc, padn);
+                               count += unsigned_num_print(unum, 10,
+                                                           padc, padn);
                                break;
                        case 's':
                                str = va_arg(args, char *);
-                               tf_string_print(str);
+                               count += tf_string_print(str);
                                break;
                        case 'p':
                                unum = (uintptr_t)va_arg(args, void *);
                                if (unum) {
-                                       tf_string_print("0x");
+                                       count += tf_string_print("0x");
                                        padn -= 2;
                                }
 
-                               unsigned_num_print(unum, 16, padc, padn);
+                               count += unsigned_num_print(unum, 16,
+                                                           padc, padn);
                                break;
                        case 'x':
                                unum = get_unum_va_args(args, l_count);
-                               unsigned_num_print(unum, 16, padc, padn);
+                               count += unsigned_num_print(unum, 16,
+                                                           padc, padn);
                                break;
                        case 'z':
                                if (sizeof(size_t) == 8)
@@ -135,7 +150,8 @@ loop:
                                goto loop;
                        case 'u':
                                unum = get_unum_va_args(args, l_count);
-                               unsigned_num_print(unum, 10, padc, padn);
+                               count += unsigned_num_print(unum, 10,
+                                                           padc, padn);
                                break;
                        case '0':
                                padc = '0';
@@ -152,20 +168,26 @@ loop:
                                }
                        default:
                                /* Exit on any other format specifier */
-                               return;
+                               return -1;
                        }
                        fmt++;
                        continue;
                }
                putchar(*fmt++);
+               count++;
        }
+
+       return count;
 }
 
-void tf_printf(const char *fmt, ...)
+int tf_printf(const char *fmt, ...)
 {
+       int count;
        va_list va;
 
        va_start(va, fmt);
-       tf_vprintf(fmt, va);
+       count = tf_vprintf(fmt, va);
        va_end(va);
+
+       return count;
 }

diff --git a/include/common/debug.h b/include/common/debug.h
index f60dfc170056f7b9b61e6ff508858220eee40475..3c99ce5016d61ece491b65b16afe496c49a5c8e1 100644 (file)
--- a/include/common/debug.h
+++ b/include/common/debug.h
@@ -90,10 +90,10 @@ void __dead2 do_panic(void);
 void __dead2 __stack_chk_fail(void);
 
 void tf_log(const char *fmt, ...) __printflike(1, 2);
-void tf_printf(const char *fmt, ...) __printflike(1, 2);
+int tf_printf(const char *fmt, ...) __printflike(1, 2);
 int tf_snprintf(char *s, size_t n, const char *fmt, ...) __printflike(3, 4);
-void tf_vprintf(const char *fmt, va_list args);
-void tf_string_print(const char *str);
+int tf_vprintf(const char *fmt, va_list args);
+int tf_string_print(const char *str);
 void tf_log_set_max_level(unsigned int log_level);
 
 #endif /* __ASSEMBLY__ */