string micro optimisations

Author: braindigitalis

src/basic/sockets.c

@@ -77,7 +77,7 @@ void sockread_statement(struct basic_ctx* ctx)
 
 	input[rv] = 0; // Null-terminate string
 
-	switch (var[strlen(var) - 1]) {
+	switch (var[var_length - 1]) {
 		case '$':
 			basic_set_string_variable(var, input, ctx, false, false);
 			break;
@@ -327,11 +327,12 @@ void udpwrite_statement(struct basic_ctx* ctx) {
 	if (source_port > 65535 || source_port < 0 || dest_port > 65535 || dest_port < 0) {
 		tokenizer_error_print(ctx, "Invalid UDP port number");
 	}
-	if (strlen(data) == 0 || strlen(data) > 65530) {
+	size_t len = strlen(data);
+	if (len == 0 || len > 65530) {
 		tokenizer_error_print(ctx, "Invalid UDP packet length");
 	}
 	uint32_t dest = htonl(str_to_ip(dest_ip));
-	udp_send_packet((uint8_t*)&dest, source_port, dest_port, (void*)data, strlen(data) + 1); // including the NULL terminator
+	udp_send_packet((uint8_t*)&dest, source_port, dest_port, (void*)data, len + 1); // including the NULL terminator
 }
 
 void udpbind_statement(struct basic_ctx* ctx) {

src/basic/variable.c

@@ -82,15 +82,12 @@ void local_statement(struct basic_ctx* ctx) {
 void newline_statement(struct basic_ctx* ctx) {
 }
 
-void assignment_statement(struct basic_ctx* ctx, bool global, bool local)
-{
+void assignment_statement(struct basic_ctx* ctx, bool global, bool local) {
 	const char* var;
 	const char* _expr;
 	double f_expr = 0;
 	size_t var_length;
 
-	basic_debug("LET statement\n");
-
 	var = tokenizer_variable_name(ctx, &var_length);
 
 	if (varname_is_int_array_access(ctx, var)) {
@@ -151,12 +148,11 @@ void assignment_statement(struct basic_ctx* ctx, bool global, bool local)
 	accept_or_return(NEWLINE, ctx);
 }
 
-bool valid_suffix_var(const char* name, char suffix)
-{
+bool valid_suffix_var(const char* name, char suffix) {
 	const char* i;
-	unsigned int varLength = strlen(name);
+	unsigned int var_length = strlen(name);
 	if (suffix != '\0') {
-		if (varLength < 2 || name[varLength - 1] != suffix) {
+		if (var_length < 2 || name[var_length - 1] != suffix) {
 			return false;
 		}
 		size_t offset = 0;
@@ -177,7 +173,7 @@ bool valid_suffix_var(const char* name, char suffix)
 		}
 		return true;
 	}
-	if (varLength < 1) {
+	if (var_length < 1) {
 		return false;
 	}
 	size_t offset = 0;

src/block/ahci/sense.c

@@ -23,7 +23,7 @@ bool atapi_request_sense6(ahci_hba_port_t* port, ahci_hba_mem_t* abar, uint8_t*
 
 	memset(cmdtbl->atapi_command, 0, sizeof(cmdtbl->atapi_command));
 	scsi_cdb_request_sense6* cdb = (scsi_cdb_request_sense6*)cmdtbl->atapi_command;
-	cdb->opcode    = SCSI_OP_REQUEST_SENSE_6; /* assumed declared in your scsi.h */
+	cdb->opcode    = SCSI_OP_REQUEST_SENSE_6;
 	cdb->alloc_len = out_len;
 
 	if (!issue_and_wait(port, slot, "request sense")) {

src/net/tcp.c

@@ -612,7 +612,6 @@ bool tcp_state_listen(ip_packet_t *encap_packet, tcp_segment_t *segment, tcp_con
 	child.snd_wnd = TCP_WINDOW_SIZE;
 	child.rcv_wnd = TCP_WINDOW_SIZE;
 
-	/* House defaults (mirror your other inits). */
 	child.fd                    = -1;
 	child.segment_list          = NULL;
 	child.recv_eof_pos          = -1;

src/string.c

@@ -36,8 +36,7 @@ int strcmp(const char* s1, const char* s2)
 	return (*(const unsigned char *)s1 - *(const unsigned char *)(s2 - 1));
 }
 
-int stricmp(const char* s1, const char* s2)
-{
+int stricmp(const char* s1, const char* s2) {
 	if (!s1 || !s2) {
 		return (int)s1 - (int)s2;
 	}
@@ -47,8 +46,7 @@ int stricmp(const char* s1, const char* s2)
 	return (*(const unsigned char *)s1 - *(const unsigned char *)(s2 - 1));
 }
 
-char* strchr(const char *s, int c)
-{
+char* strchr(const char *s, int c) {
 	if (!s) {
 		return NULL;
 	}
@@ -88,35 +86,26 @@ int strnicmp(const char* s1, const char* s2, uint32_t n)
 
 #include <stdint.h>
 
-__attribute__((hot)) int strncmp(const char *s1, const char *s2, uint32_t n)
-{
+__attribute__((hot)) int strncmp(const char *s1, const char *s2, uint32_t n) {
 	if (!s1 || !s2) {
-		return (int)s1 - (int)s2; /* preserve your NULL behaviour */
+		return (int)s1 - (int)s2;
 	}
-
 	if (s1 == s2 || n == 0) {
 		return 0;
 	}
-
 	const unsigned char *p1 = (const unsigned char *)s1;
 	const unsigned char *p2 = (const unsigned char *)s2;
-
 	while (n--) {
 		unsigned char a = *p1++;
 		unsigned char b = *p2++;
-
-		/* Common case: bytes equal and not NUL → continue. */
 		if (__builtin_expect(a == b, 1)) {
 			if (__builtin_expect(a != 0u, 1)) {
 				continue;
 			}
-			return 0; /* both NUL at same position */
+			return 0;
 		}
-
-		/* First difference decides the result. */
 		return (int)a - (int)b;
 	}
-
 	return 0;
 }