free-standing environment: remove fluff from the argv/envp parsing facility.

1 files changed, 15 insertions, 78 deletions

diff --git a/src/argv/ntapi_tt_env_vars.c b/src/argv/ntapi_tt_env_vars.c
index 4fe590c..5642101 100644
--- a/src/argv/ntapi_tt_env_vars.c
+++ b/src/argv/ntapi_tt_env_vars.c
@@ -9,104 +9,41 @@
 #include "ntapi_impl.h"
 
 int32_t __stdcall __ntapi_tt_get_env_var_meta_utf16(
-	__in	const uint32_t *	crc32_table,
 	__in	wchar16_t *		env_var_name,
-	__in	uint32_t		env_var_name_hash __optional,
 	__in	wchar16_t **		envp,
 	__out	nt_env_var_meta_utf16 *	env_var_meta)
 {
 	int		idx;
-	uint32_t	crc32;
-	unsigned char *	byte_buffer;
 	wchar16_t *	wch;
 
-	#define EQUAL_SIGN	0x3D
+	#define EQUAL_SIGN 0x3D
 
-	/* step 1: crc32 of the target env_var_name */
-	if (env_var_name_hash)
-		crc32 = env_var_name_hash;
-	else {
-		crc32 = 0 ^ 0xFFFFFFFF;
+	/* init */
+	env_var_meta->name       = 0;
+	env_var_meta->value      = 0;
+	env_var_meta->envp_index = 0;
+	env_var_meta->flags      = 0;
 
-		/* initialize byte_buffer */
-		byte_buffer = (unsigned char *)env_var_name;
-
-		/* iterate */
-		while (*byte_buffer) {
-			/* two bytes at a time */
-			crc32 = (crc32 >> 8) ^ crc32_table[(crc32 ^ *byte_buffer) & 0xFF];
-			byte_buffer++;
-			crc32 = (crc32 >> 8) ^ crc32_table[(crc32 ^ *byte_buffer) & 0xFF];
-			byte_buffer++;
-		}
-		crc32 = (crc32 ^ 0xFFFFFFFF);
-	}
-
-	/* initialize the env_var_meta structure */
-	env_var_meta->name_hash		= crc32;
-	env_var_meta->name		= (wchar16_t *)0;
-	env_var_meta->value		= (wchar16_t *)0;
-	env_var_meta->value_hash	= 0;
-	env_var_meta->envp_index	= 0;
-	env_var_meta->flags		= 0;
-
-	/* step 2: look for the environment variable in envp[] */
-	idx = 0;
-	while (envp[idx] && (!env_var_meta->value)) {
+	/* lookup */
+	for (idx=0; envp[idx] && !env_var_meta->value; idx++) {
 		wch = envp[idx];
 
-		/* find the equal sign */
-		while ((*wch) && (*wch != EQUAL_SIGN))
+		while (*wch && (*wch != EQUAL_SIGN))
 			wch++;
 
 		if (*wch != EQUAL_SIGN)
 			return NT_STATUS_ILLEGAL_CHARACTER;
 
-		/* hash the current environment variable */
-		crc32 = 0 ^ 0xFFFFFFFF;
-
-		/* initialize byte_buffer */
-		byte_buffer = (unsigned char *)envp[idx];
-
-		/* iterate */
-		while ((uintptr_t)(byte_buffer) < (uintptr_t)wch) {
-			/* two bytes at a time */
-			crc32 = (crc32 >> 8) ^ crc32_table[(crc32 ^ *byte_buffer) & 0xFF];
-			byte_buffer++;
-			crc32 = (crc32 >> 8) ^ crc32_table[(crc32 ^ *byte_buffer) & 0xFF];
-			byte_buffer++;
-		}
-
-		if (env_var_meta->name_hash == (crc32 ^ 0xFFFFFFFF)) {
-			/* found it, get ready to hash the value */
+		if (!(__ntapi->tt_strncmp_utf16(
+				envp[idx],
+				env_var_name,
+				wch - envp[idx]))) {
 			wch++;
-			env_var_meta->name	 = envp[idx];
-			env_var_meta->value	 = wch;
+			env_var_meta->name       = envp[idx];
+			env_var_meta->value      = wch;
 			env_var_meta->envp_index = idx;
-		} else {
-			idx++;
-		}
-	}
-
-	if (env_var_meta->value) {
-		/* hash the value: utf-16, null-terminated */
-		crc32 = 0 ^ 0xFFFFFFFF;
-
-		/* initialize byte_buffer */
-		byte_buffer = (unsigned char *)env_var_meta->value;
-
-		/* iterate */
-		while (*byte_buffer) {
-			/* two bytes at a time */
-			crc32 = (crc32 >> 8) ^ crc32_table[(crc32 ^ *byte_buffer) & 0xFF];
-			byte_buffer++;
-			crc32 = (crc32 >> 8) ^ crc32_table[(crc32 ^ *byte_buffer) & 0xFF];
-			byte_buffer++;
 		}
-
-		env_var_meta->value_hash = (crc32 ^ 0xFFFFFFFF);
 	}
 
 	return NT_STATUS_SUCCESS;
 }
-