Added packing and unpacking operations

include/sv.h

@@ -28,5 +28,7 @@ extern struct String_View sv_after_delim(const struct String_View sv,
         const char *delims);
 extern struct String_View sv_str_str(const struct String_View haystack, 
         const struct String_View needle);
-
+extern size_t sv_pack_size(const struct String_View sv);
+extern void sv_pack(unsigned char *buf, const struct String_View sv);
+extern struct String_View sv_unpack(unsigned char *buf);
 #endif

src/sv.c

@@ -1,7 +1,8 @@
 #include "../include/sv.h"
 #include <string.h>
-
 #include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
 
 static bool sv_is_space(int c) {
     return c == ' ' || c == '\t' || c == '\n' || c == '\r' || c == '\v' || c == '\f';
@@ -9,7 +10,26 @@ static bool sv_is_space(int c) {
 static int sv_tolc(char c) {
     return (c >= 'A' && c <= 'Z') ? c + 'a' - 'A' : c;
 }
-
+static void sv_pack_u64(uint64_t i, unsigned char *buf){
+    *buf++ = i>>56; 
+    *buf++ = i>>48;
+	*buf++ = i>>40; 
+    *buf++ = i>>32;
+	*buf++ = i>>24; 
+    *buf++ = i>>16;
+	*buf++ = i>>8;  
+    *buf++ = i;
+}
+static uint64_t sv_unpack_u64(unsigned char *buf){
+return ((unsigned long long int)buf[0]<<56) |
+	       ((unsigned long long int)buf[1]<<48) |
+	       ((unsigned long long int)buf[2]<<40) |
+	       ((unsigned long long int)buf[3]<<32) |
+	       ((unsigned long long int)buf[4]<<24) |
+	       ((unsigned long long int)buf[5]<<16) |
+	       ((unsigned long long int)buf[6]<<8)  |
+	       buf[7];
+}
 struct String_View sv_str(const char *s) {
     struct String_View str = {s == NULL ? 0 : strlen(s), (char *) s };
     return str;
@@ -115,3 +135,18 @@ struct String_View sv_str_str(const struct String_View haystack, const struct St
     return sv_strn(NULL,0);
 }
 
+size_t sv_pack_size(const struct String_View sv){
+    size_t result = 0;
+    result += sv.len;
+    result += sizeof(uint64_t);
+    return result;
+}
+void sv_pack(unsigned char *buf, const struct String_View sv){
+    sv_pack_u64(sv.len, buf);
+    size_t offset = sizeof(uint64_t);
+    memcpy(buf+offset, sv.buf, sv.len);    
+}
+struct String_View sv_unpack(unsigned char *buf){
+    size_t len = sv_unpack_u64(buf);
+    return sv_strn((const char *)buf+sizeof(uint64_t),len);    
+}

tests/11_sv_pack.c

@@ -0,0 +1,24 @@
+#define DEBUG
+#include <stdlib.h>
+#include <assert.h>
+#include <string.h>
+#include <stdint.h>
+#include <stdio.h>
+#include "../include/sv.h"
+
+int main(void){
+    const char *s = "Hello";
+    struct String_View sv = sv_strn(s, strlen(s));
+    size_t offset = sv_pack_size(sv);
+    unsigned char *buf = malloc(offset);
+    
+    sv_pack(buf, sv);
+
+    struct String_View out = sv_unpack(buf);
+    assert(out.len == strlen(s));
+    assert( memcmp(out.buf, s, out.len) == 0);
+    assert( sv_eq(sv, out));
+    assert( sv_casecmp(sv, out ) == 0);
+    free(buf);
+    return EXIT_SUCCESS;
+}

tests/12_sv_pack2.c

@@ -0,0 +1,21 @@
+#define DEBUG
+#include <stdlib.h>
+#include <assert.h>
+#include <string.h>
+#include <stdint.h>
+#include <stdio.h>
+#include "../include/sv.h"
+
+int main(void){
+    const char *s = "Hello";
+    size_t offset = strlen(s) + sizeof(uint64_t);
+    unsigned char *buf = malloc(offset);
+    struct String_View sv = sv_strn(s, strlen(s));
+    sv_pack(buf, sv);
+    
+    struct String_View out = sv_unpack(buf);
+    assert(out.len == strlen(s));
+    assert( memcmp(out.buf, s, out.len) == 0);
+    free(buf);
+    return EXIT_SUCCESS;
+}