Simplify num2str()

Instead of translating the N2S_* constants into an array index inside
num2str(), make the N2S_* constants identical to the array index used
inside num2str(). This patch does not change the behavior of num2str().

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>

diff --git a/lib/num2str.c b/lib/num2str.c
index 71d65e04fe7730a777e5eb249b4a9e043cb944d6..40fb3aec923d3ce6199b64d0cf4c791c92e2151a 100644 (file)
--- a/lib/num2str.c
+++ b/lib/num2str.c
@@ -22,14 +22,22 @@ char *num2str(uint64_t num, int maxlen, int base, int pow2, enum n2s_unit units)
        const char *sistr[] = { "", "k", "M", "G", "T", "P" };
        const char *iecstr[] = { "", "Ki", "Mi", "Gi", "Ti", "Pi" };
        const char **unitprefix;
-       const char *unitstr[] = { "", "/s", "B", "bit", "B/s", "bit/s" };
+       static const char *const unitstr[] = {
+               [N2S_NONE]      = "",
+               [N2S_PERSEC]    = "/s",
+               [N2S_BYTE]      = "B",
+               [N2S_BIT]       = "bit",
+               [N2S_BYTEPERSEC]= "B/s",
+               [N2S_BITPERSEC] = "bit/s"
+       };
        const unsigned int thousand[] = { 1000, 1024 };
        unsigned int modulo;
-       int unit_index = 0, post_index, carry = 0;
+       int post_index, carry = 0;
        char tmp[32], fmt[32];
        char *buf;
 
        compiletime_assert(sizeof(sistr) == sizeof(iecstr), "unit prefix arrays must be identical sizes");
+       assert(units < ARRAY_SIZE(unitstr));
 
        buf = malloc(128);
        if (!buf)
@@ -47,20 +55,15 @@ char *num2str(uint64_t num, int maxlen, int base, int pow2, enum n2s_unit units)
        case N2S_NONE:
                break;
        case N2S_PERSEC:
-               unit_index = 1;
                break;
        case N2S_BYTE:
-               unit_index = 2;
                break;
        case N2S_BIT:
-               unit_index = 3;
                num *= 8;
                break;
        case N2S_BYTEPERSEC:
-               unit_index = 4;
                break;
        case N2S_BITPERSEC:
-               unit_index = 5;
                num *= 8;
                break;
        }
@@ -89,7 +92,7 @@ done:
                        post_index = 0;
 
                sprintf(buf, "%llu%s%s", (unsigned long long) num,
-                       unitprefix[post_index], unitstr[unit_index]);
+                       unitprefix[post_index], unitstr[units]);
                return buf;
        }
 
@@ -112,6 +115,6 @@ done:
        sprintf(tmp, fmt, (double)modulo / (double)thousand[!!pow2]);
 
        sprintf(buf, "%llu.%s%s%s", (unsigned long long) num, &tmp[2],
-                       unitprefix[post_index], unitstr[unit_index]);
+                       unitprefix[post_index], unitstr[units]);
        return buf;
 }

diff --git a/lib/num2str.h b/lib/num2str.h
index ad61e2408248f7865fcc4dc1dcbb5363f4f0619e..797288b5af891a616a082f161ac1fb32d6e663f9 100644 (file)
--- a/lib/num2str.h
+++ b/lib/num2str.h
@@ -5,11 +5,11 @@
 
 enum n2s_unit {
        N2S_NONE        = 0,
-       N2S_BITPERSEC   = 1,
-       N2S_PERSEC      = 2,
+       N2S_PERSEC      = 1,
+       N2S_BYTE        = 2,
        N2S_BIT         = 3,
-       N2S_BYTE        = 4,
-       N2S_BYTEPERSEC  = 8,
+       N2S_BYTEPERSEC  = 4,
+       N2S_BITPERSEC   = 5,
 };
 
 extern char *num2str(uint64_t, int, int, int, enum n2s_unit);