Add a DJB2 string hashing function

include/akstdlib.h

@@ -5,6 +5,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <stdint.h>
 
 akerr_ErrorContext AKERR_NOIGNORE *aksl_fopen(char *pathname, char *mode, FILE **fp);
 akerr_ErrorContext AKERR_NOIGNORE *aksl_fread(void *ptr, size_t size, size_t nmemb, FILE *stream);
@@ -24,7 +25,10 @@ akerr_ErrorContext AKERR_NOIGNORE *aksl_sprintf(int *count, char *restrict str,
 akerr_ErrorContext AKERR_NOIGNORE *aksl_atoi(const char *nptr, int *dest);
 akerr_ErrorContext AKERR_NOIGNORE *aksl_atol(const char *nptr, long *dest);
 akerr_ErrorContext AKERR_NOIGNORE *aksl_atoll(const char *nptr, long long *dest);
+akerr_ErrorContext AKERR_NOIGNORE *aksl_atof(const char *nptr, double *dest);
 
 akerr_ErrorContext AKERR_NOIGNORE *aksl_realpath(const char *restrict path, char *restrict resolved_path);
 
+akerr_ErrorContext AKERR_NOIGNORE *aksl_strhash_djb2(char *str, size_t len, uint32_t *hashval);
+
 #endif

src/stdlib.c

@@ -3,6 +3,8 @@
 #include <stdlib.h>
 #include <errno.h>
 #include <string.h>
+#include <stdarg.h>
+#include <stdint.h>
 
 akerr_ErrorContext AKERR_NOIGNORE *aksl_malloc(size_t size, void **dst)
 {
@@ -122,6 +124,7 @@ akerr_ErrorContext AKERR_NOIGNORE *aksl_sprintf(int *count, char *restrict str,
     FAIL_ZERO_RETURN(e, count, AKERR_NULLPOINTER, "count=%p, str=%p, format=%p", (void *)count, (void *)str, (void *)format);
     FAIL_ZERO_RETURN(e, str, AKERR_NULLPOINTER, "count=%p, str=%p, format=%p", (void *)count, (void *)str, (void *)format);
     FAIL_ZERO_RETURN(e, format, AKERR_NULLPOINTER, "count=%p, str=%p, format=%p", (void *)count, (void *)str, (void *)format);
+    va_start(args, format);
     *count = vsprintf(str, format, args);
     FAIL_NONZERO_RETURN(e, (*count == -1), errno, "Short write");
     SUCCEED_RETURN(e);
@@ -154,12 +157,34 @@ akerr_ErrorContext AKERR_NOIGNORE *aksl_atoll(const char *nptr, long long *dest)
     SUCCEED_RETURN(e);
 }
 
+akerr_ErrorContext AKERR_NOIGNORE *aksl_atof(const char *nptr, double *dest)
+{
+    PREPARE_ERROR(e);
+    FAIL_ZERO_RETURN(e, nptr, AKERR_NULLPOINTER, "nptr=%p, dest=%p", (void *)nptr, (void *)dest);
+    FAIL_ZERO_RETURN(e, dest, AKERR_NULLPOINTER, "nptr=%p, dest=%p", (void *)nptr, (void *)dest);
+    *dest = atof(nptr);
+    SUCCEED_RETURN(e);
+}
+
 akerr_ErrorContext AKERR_NOIGNORE *aksl_realpath(const char *restrict path, char *restrict resolved_path)
 {
     char *result = NULL;
     PREPARE_ERROR(e);
     FAIL_ZERO_RETURN(e, path, AKERR_NULLPOINTER, "path=%p, dest=%p", (void *)path, (void *)resolved_path);
     result = realpath(path, resolved_path);
-    FAIL_ZERO_RETURN(e, result, errno, "Error");
+    FAIL_ZERO_RETURN(e, result, errno, "path=%s, dest=%s", path, resolved_path);
+    SUCCEED_RETURN(e);
+}
+
+akerr_ErrorContext AKERR_NOIGNORE *aksl_strhash_djb2(char *str, size_t len, uint32_t *hashval)
+{
+    PREPARE_ERROR(e);
+    FAIL_ZERO_RETURN(e, str, AKERR_NULLPOINTER, "str");
+    FAIL_ZERO_RETURN(e, hashval, AKERR_NULLPOINTER, "hashval");
+    uint32_t h = 5381;
+    while (len--) {
+	h = ((h << 5) + h) + *str++;
+    }
+    *hashval = h;
     SUCCEED_RETURN(e);
 }