Add big integer function to quickly generate power of 10 number

2 files changed, 132 insertions, 0 deletions

diff --git a/include/bh/bigint.h b/include/bh/bigint.h
index c9cd6e0..5d0833d 100644
--- a/include/bh/bigint.h
+++ b/include/bh/bigint.h
@@ -92,6 +92,9 @@ int bh_bigint_pow(bh_bigint_t *to,
                   bh_bigint_t *from,
                   bh_uint32_t power);
 
+int bh_bigint_pow10(bh_bigint_t *to,
+                    bh_uint32_t power);
+
 int bh_bigint_powm(bh_bigint_t *to,
                   bh_bigint_t *left,
                   bh_bigint_t *right,
diff --git a/src/bigint.c b/src/bigint.c
index c78503d..a935461 100644
--- a/src/bigint.c
+++ b/src/bigint.c
@@ -796,6 +796,135 @@ finish:
     return code;
 }
 
+#if defined(BH_BIGINT_LONG)
+const size_t bh_bigint_pow10_e[] =
+{
+    512, 256, 128, 64, 32, 16, 8, 4, 2, 1
+};
+
+const size_t bh_bigint_pow10_size[] =
+{
+    55, 28, 14, 7, 4, 2, 1, 1, 1, 1
+};
+
+const size_t bh_bigint_pow10_offset[] =
+{
+    0, 55, 83, 97, 104, 108, 110, 111, 112, 113
+};
+
+const BH_BIGINT_TYPE bh_bigint_pow10_data[] =
+{
+    0x00000000ul, 0x00000000ul, 0x00000000ul, 0x00000000ul,
+    0x00000000ul, 0x00000000ul, 0x00000000ul, 0x00000000ul,
+    0x00000000ul, 0x00000000ul, 0x00000000ul, 0x00000000ul,
+    0x00000000ul, 0x00000000ul, 0x00000000ul, 0x00000000ul,
+    0x78010000ul, 0x64CFF8D9ul, 0x1B71DFC9ul, 0x3B7C7CAAul,
+    0x2975D969ul, 0x5B370751ul, 0x44F0C786ul, 0x23A36202ul,
+    0x4194E657ul, 0x739112EDul, 0x6D11D6D5ul, 0x7947C399ul,
+    0x1AA1DA1Bul, 0x4E07DA64ul, 0x078973FAul, 0x590D1791ul,
+    0x3C51FB2Eul, 0x2DC29EBBul, 0x7E8FB6B2ul, 0x14E2BD75ul,
+    0x7FC71533ul, 0x7F80D2BCul, 0x6A464930ul, 0x2FB1AF42ul,
+    0x108EE0F9ul, 0x575BC965ul, 0x19CCAA4Eul, 0x4BBAE09Bul,
+    0x65B0E944ul, 0x75F58D37ul, 0x6F205CD0ul, 0x0EA3584Cul,
+    0x174845A7ul, 0x660744D3ul, 0x7C4E32C1ul, 0x54BC5058ul,
+    0x0D98CAB8ul, 0x3A983A47ul, 0x0718CD05ul, 0x00000000ul,
+    0x00000000ul, 0x00000000ul, 0x00000000ul, 0x00000000ul,
+    0x00000000ul, 0x00000000ul, 0x00000000ul, 0x2E7C0100ul,
+    0x270EB730ul, 0x667DCAFBul, 0x297C3EC6ul, 0x650C6121ul,
+    0x4DCE0D7Bul, 0x7603F3D2ul, 0x38B76ACAul, 0x66B026B2ul,
+    0x6C495B8Cul, 0x4D687454ul, 0x2071E216ul, 0x3C063FF5ul,
+    0x62F98AAEul, 0x3C997E7Bul, 0x7BAADE14ul, 0x5C80DCC7ul,
+    0x1DE8DDDBul, 0x5D7F73BFul, 0x00002A9Ful, 0x00000000ul,
+    0x00000000ul, 0x00000000ul, 0x00000000ul, 0x6953E010ul,
+    0x7BF32125ul, 0x454E3F40ul, 0x3A721787ul, 0x4FF5EC23ul,
+    0x09B811A7ul, 0x36C36B10ul, 0x1BF8CDE6ul, 0x72603A63ul,
+    0x0049DD23ul, 0x00000000ul, 0x00000000ul, 0x7DA87C04ul,
+    0x71C76B25ul, 0x2A797ED6ul, 0x27FF3E9Bul, 0x0613C0FAul,
+    0x00000000ul, 0x0B59DF02ul, 0x35B5056Eul, 0x00002771ul,
+    0x6FC10000ul, 0x00470DE4ul, 0x05F5E100ul, 0x00002710ul,
+    0x00000064ul, 0x0000000Aul
+};
+#else
+const size_t bh_bigint_pow10_e[] =
+{
+    512, 256, 128, 64, 32, 16, 8, 4, 2, 1
+};
+const size_t bh_bigint_pow10_size[] =
+{
+    114, 57, 29, 15, 8, 4, 2, 1, 1, 1
+};
+const size_t bh_bigint_pow10_offset[] =
+{
+    0, 114, 171, 200, 215, 223, 227, 229, 230, 231
+};
+const BH_BIGINT_TYPE bh_bigint_pow10_data[] =
+{
+    0x0000u, 0x0000u, 0x0000u, 0x0000u, 0x0000u, 0x0000u, 0x0000u, 0x0000u,
+    0x0000u, 0x0000u, 0x0000u, 0x0000u, 0x0000u, 0x0000u, 0x0000u, 0x0000u,
+    0x0000u, 0x0000u, 0x0000u, 0x0000u, 0x0000u, 0x0000u, 0x0000u, 0x0000u,
+    0x0000u, 0x0000u, 0x0000u, 0x0000u, 0x0000u, 0x0000u, 0x0000u, 0x0000u,
+    0x0000u, 0x0000u, 0x6004u, 0x6367u, 0x267Fu, 0x7E4Eu, 0x371Du, 0x4AA3u,
+    0x6F8Fu, 0x2D2Eu, 0x5D76u, 0x5454u, 0x1B83u, 0x435Bu, 0x70C7u, 0x0289u,
+    0x46C4u, 0x2E8Eu, 0x5399u, 0x360Cu, 0x0897u, 0x2F39u, 0x1D6Du, 0x1DA2u,
+    0x7873u, 0x7E51u, 0x7686u, 0x0D50u, 0x6D32u, 0x4E07u, 0x73FAu, 0x0F12u,
+    0x2F22u, 0x6434u, 0x6CBAu, 0x628Fu, 0x75DBu, 0x5C29u, 0x6B25u, 0x51F6u,
+    0x2EBFu, 0x38AFu, 0x4CCAu, 0x638Au, 0x5E7Fu, 0x00D2u, 0x30FFu, 0x0C92u,
+    0x05A9u, 0x46BDu, 0x657Du, 0x7707u, 0x2908u, 0x3C96u, 0x6AEBu, 0x1549u,
+    0x6673u, 0x3826u, 0x25DDu, 0x74A2u, 0x65B0u, 0x0D37u, 0x6BEBu, 0x39A1u,
+    0x3C81u, 0x6133u, 0x751Au, 0x2D38u, 0x7484u, 0x4D32u, 0x40E8u, 0x5839u,
+    0x138Cu, 0x163Eu, 0x5E28u, 0x5C54u, 0x18CAu, 0x471Bu, 0x3074u, 0x0AEAu,
+    0x6334u, 0x0038u, 0x0000u, 0x0000u, 0x0000u, 0x0000u, 0x0000u, 0x0000u,
+    0x0000u, 0x0000u, 0x0000u, 0x0000u, 0x0000u, 0x0000u, 0x0000u, 0x0000u,
+    0x0000u, 0x0000u, 0x0000u, 0x7802u, 0x60B9u, 0x3ADCu, 0x6D38u, 0x6E57u,
+    0x3667u, 0x43ECu, 0x152Fu, 0x0C24u, 0x7943u, 0x035Eu, 0x26E7u, 0x79E9u,
+    0x7603u, 0x6ACAu, 0x716Eu, 0x4D64u, 0x1AC0u, 0x6E33u, 0x624Au, 0x22A6u,
+    0x5687u, 0x2169u, 0x0E3Cu, 0x7EA8u, 0x018Fu, 0x2B9Eu, 0x7CC5u, 0x3DE2u,
+    0x197Eu, 0x1479u, 0x55BCu, 0x0FEEu, 0x0373u, 0x6EE4u, 0x46EEu, 0x79DEu,
+    0x773Bu, 0x7BAFu, 0x0553u, 0x0000u, 0x0000u, 0x0000u, 0x0000u, 0x0000u,
+    0x0000u, 0x0000u, 0x0000u, 0x0100u, 0x2A7Cu, 0x24BAu, 0x7CC8u, 0x503Du,
+    0x271Fu, 0x43C5u, 0x7217u, 0x2374u, 0x6BD8u, 0x4F3Fu, 0x6046u, 0x404Du,
+    0x1B58u, 0x336Cu, 0x0CDEu, 0x337Fu, 0x074Cu, 0x7C98u, 0x7748u, 0x0024u,
+    0x0000u, 0x0000u, 0x0000u, 0x0000u, 0x7010u, 0x6D43u, 0x592Fu, 0x1C76u,
+    0x6D6Eu, 0x4F2Fu, 0x536Au, 0x7FCFu, 0x3E93u, 0x09E0u, 0x0006u, 0x0000u,
+    0x0000u, 0x3E04u, 0x2D67u, 0x15B8u, 0x2DA8u, 0x3B8Bu, 0x0002u, 0x0000u,
+    0x5F82u, 0x1BC9u, 0x011Cu, 0x6100u, 0x0BEBu, 0x2710u, 0x0064u, 0x000Au
+};
+#endif
+
+int bh_bigint_pow10(bh_bigint_t *to,
+                    bh_uint32_t power)
+{
+    size_t index;
+
+    /* Check if exponent withing lookup index range (times 2) */
+    if ((power >= 1024) || 0)
+    {
+        bh_bigint_set_int(to, 10);
+        return bh_bigint_pow(to, to, power);
+    }
+
+    /* Use lookup table */
+    bh_bigint_set_int(to, 1);
+    for (index = 0; (index < sizeof(bh_bigint_pow10_e) / sizeof(size_t)) || power; index++)
+    {
+        if (power >= bh_bigint_pow10_e[index])
+        {
+            bh_bigint_t tmp;
+
+            tmp.data = &bh_bigint_pow10_data[bh_bigint_pow10_offset[index]];
+            tmp.capacity = bh_bigint_pow10_size[index];
+            tmp.size = bh_bigint_pow10_size[index];
+            tmp.type = 1;
+            tmp.error = 0;
+
+            bh_bigint_mul(to, to, &tmp);
+            power -= bh_bigint_pow10_e[index];
+        }
+    }
+
+    return BH_OK;
+}
+
 int bh_bigint_powm(bh_bigint_t *to,
                    bh_bigint_t *left,
                    bh_bigint_t *right,