i2c-tools: Use getopt

Use the standard C getopt() function instead of parsing the options
manually. The benefit of this move is that getopt() supports merged
flags (for example -fy instead of -f -y) and does not require options
to come first on the command line. As this is pretty standard by now,
not supporting such possibilities can confuse and disappoint the user.

Based on a preliminary patch from David Kerns.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>

5 files changed, 76 insertions, 94 deletions

diff --git a/tools/i2cdetect.c b/tools/i2cdetect.c
index 1f34b56..8f4f5f9 100644
--- a/tools/i2cdetect.c
+++ b/tools/i2cdetect.c
@@ -2,7 +2,7 @@
     i2cdetect.c - a user-space program to scan for I2C devices
     Copyright (C) 1999-2004  Frodo Looijaard <frodol@dds.nl>, and
                              Mark D. Studebaker <mdsxyz123@yahoo.com>
-    Copyright (C) 2004-2012  Jean Delvare <jdelvare@suse.de>
+    Copyright (C) 2004-2022  Jean Delvare <jdelvare@suse.de>
 
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -205,12 +205,12 @@ int main(int argc, char *argv[])
 	unsigned long funcs;
 	int mode = MODE_AUTO;
 	int first = 0x08, last = 0x77;
-	int flags = 0;
+	int opt;
 	int yes = 0, version = 0, list = 0;
 
 	/* handle (optional) flags first */
-	while (1+flags < argc && argv[1+flags][0] == '-') {
-		switch (argv[1+flags][1]) {
+	while ((opt = getopt(argc, argv, "FValqry")) != -1) {
+		switch (opt) {
 		case 'V': version = 1; break;
 		case 'y': yes = 1; break;
 		case 'l': list = 1; break;
@@ -242,13 +242,10 @@ int main(int argc, char *argv[])
 			first = 0x00;
 			last = 0x7F;
 			break;
-		default:
-			fprintf(stderr, "Error: Unsupported option "
-				"\"%s\"!\n", argv[1+flags]);
+		case '?':
 			help();
 			exit(1);
 		}
-		flags++;
 	}
 
 	if (version) {
@@ -261,22 +258,22 @@ int main(int argc, char *argv[])
 		exit(0);
 	}
 
-	if (argc < flags + 2) {
+	if (argc < optind + 1) {
 		fprintf(stderr, "Error: No i2c-bus specified!\n");
 		help();
 		exit(1);
 	}
-	i2cbus = lookup_i2c_bus(argv[flags+1]);
+	i2cbus = lookup_i2c_bus(argv[optind]);
 	if (i2cbus < 0) {
 		help();
 		exit(1);
 	}
 
 	/* read address range if present */
-	if (argc == flags + 4 && mode != MODE_FUNC) {
+	if (argc == optind + 3 && mode != MODE_FUNC) {
 		int tmp;
 
-		tmp = strtol(argv[flags+2], &end, 0);
+		tmp = strtol(argv[optind+1], &end, 0);
 		if (*end) {
 			fprintf(stderr, "Error: FIRST argument not a "
 				"number!\n");
@@ -291,7 +288,7 @@ int main(int argc, char *argv[])
 		}
 		first = tmp;
 
-		tmp = strtol(argv[flags+3], &end, 0);
+		tmp = strtol(argv[optind+2], &end, 0);
 		if (*end) {
 			fprintf(stderr, "Error: LAST argument not a "
 				"number!\n");
@@ -305,7 +302,7 @@ int main(int argc, char *argv[])
 			exit(1);
 		}
 		last = tmp;
-	} else if (argc != flags + 2) {
+	} else if (argc != optind + 1) {
 		help();
 		exit(1);
 	}
diff --git a/tools/i2cdump.c b/tools/i2cdump.c
index e7dfaf1..1082211 100644
--- a/tools/i2cdump.c
+++ b/tools/i2cdump.c
@@ -2,7 +2,7 @@
     i2cdump.c - a user-space program to dump I2C registers
     Copyright (C) 2002-2003  Frodo Looijaard <frodol@dds.nl>, and
                              Mark D. Studebaker <mdsxyz123@yahoo.com>
-    Copyright (C) 2004-2021  Jean Delvare <jdelvare@suse.de>
+    Copyright (C) 2004-2022  Jean Delvare <jdelvare@suse.de>
 
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -110,26 +110,23 @@ int main(int argc, char *argv[])
 	char filename[20];
 	int block[256];
 	int pec = 0, even = 0;
-	int flags = 0;
+	int opt;
 	int force = 0, yes = 0, version = 0, all_addrs = 0;
 	const char *range = NULL;
 	int first = 0x00, last = 0xff;
 
 	/* handle (optional) flags first */
-	while (1+flags < argc && argv[1+flags][0] == '-') {
-		switch (argv[1+flags][1]) {
+	while ((opt = getopt(argc, argv, "Vafr:y")) != -1) {
+		switch (opt) {
 		case 'V': version = 1; break;
 		case 'f': force = 1; break;
-		case 'r': range = argv[1+(++flags)]; break;
+		case 'r': range = optarg; break;
 		case 'y': yes = 1; break;
 		case 'a': all_addrs = 1; break;
-		default:
-			fprintf(stderr, "Error: Unsupported option "
-				"\"%s\"!\n", argv[1+flags]);
+		case '?':
 			help();
 			exit(1);
 		}
-		flags++;
 	}
 
 	if (version) {
@@ -137,48 +134,48 @@ int main(int argc, char *argv[])
 		exit(0);
 	}
 
-	if (argc < flags + 2) {
+	if (argc < optind + 1) {
 		fprintf(stderr, "Error: No i2c-bus specified!\n");
 		help();
 		exit(1);
 	}
-	i2cbus = lookup_i2c_bus(argv[flags+1]);
+	i2cbus = lookup_i2c_bus(argv[optind]);
 	if (i2cbus < 0) {
 		help();
 		exit(1);
 	}
 
-	if (argc < flags + 3) {
+	if (argc < optind + 2) {
 		fprintf(stderr, "Error: No address specified!\n");
 		help();
 		exit(1);
 	}
-	address = parse_i2c_address(argv[flags+2], all_addrs);
+	address = parse_i2c_address(argv[optind+1], all_addrs);
 	if (address < 0) {
 		help();
 		exit(1);
 	}
 
-	if (argc < flags + 4) {
+	if (argc < optind + 3) {
 		fprintf(stderr, "No size specified (using byte-data access)\n");
 		size = I2C_SMBUS_BYTE_DATA;
-	} else if (!strncmp(argv[flags+3], "b", 1)) {
+	} else if (!strncmp(argv[optind+2], "b", 1)) {
 		size = I2C_SMBUS_BYTE_DATA;
-		pec = argv[flags+3][1] == 'p';
-	} else if (!strncmp(argv[flags+3], "w", 1)) {
+		pec = argv[optind+2][1] == 'p';
+	} else if (!strncmp(argv[optind+2], "w", 1)) {
 		size = I2C_SMBUS_WORD_DATA;
-		pec = argv[flags+3][1] == 'p';
-	} else if (!strncmp(argv[flags+3], "W", 1)) {
+		pec = argv[optind+2][1] == 'p';
+	} else if (!strncmp(argv[optind+2], "W", 1)) {
 		size = I2C_SMBUS_WORD_DATA;
 		even = 1;
-	} else if (!strncmp(argv[flags+3], "s", 1)) {
+	} else if (!strncmp(argv[optind+2], "s", 1)) {
 		fprintf(stderr,
 			"SMBus block mode is no longer supported, please use i2cget instead\n");
 		exit(1);
-	} else if (!strncmp(argv[flags+3], "c", 1)) {
+	} else if (!strncmp(argv[optind+2], "c", 1)) {
 		size = I2C_SMBUS_BYTE;
-		pec = argv[flags+3][1] == 'p';
-	} else if (!strcmp(argv[flags+3], "i"))
+		pec = argv[optind+2][1] == 'p';
+	} else if (!strcmp(argv[optind+2], "i"))
 		size = I2C_SMBUS_I2C_BLOCK_DATA;
 	else {
 		fprintf(stderr, "Error: Invalid mode!\n");
@@ -186,8 +183,8 @@ int main(int argc, char *argv[])
 		exit(1);
 	}
 
-	if (argc > flags + 4) {
-		bank = strtol(argv[flags+4], &end, 0);
+	if (argc > optind + 3) {
+		bank = strtol(argv[optind+3], &end, 0);
 		if (*end || size == I2C_SMBUS_I2C_BLOCK_DATA) {
 			fprintf(stderr, "Error: Invalid bank number!\n");
 			help();
@@ -200,8 +197,8 @@ int main(int argc, char *argv[])
 			exit(1);
 		}
 
-		if (argc > flags + 5) {
-			bankreg = strtol(argv[flags+5], &end, 0);
+		if (argc > optind + 4) {
+			bankreg = strtol(argv[optind+4], &end, 0);
 			if (*end) {
 				fprintf(stderr, "Error: Invalid bank register "
 					"number!\n");
diff --git a/tools/i2cget.c b/tools/i2cget.c
index 38bd44a..1d9fdff 100644
--- a/tools/i2cget.c
+++ b/tools/i2cget.c
@@ -1,6 +1,6 @@
 /*
     i2cget.c - A user-space program to read an I2C register.
-    Copyright (C) 2005-2021  Jean Delvare <jdelvare@suse.de>
+    Copyright (C) 2005-2022  Jean Delvare <jdelvare@suse.de>
 
     Based on i2cset.c:
     Copyright (C) 2001-2003  Frodo Looijaard <frodol@dds.nl>, and
@@ -180,25 +180,22 @@ int main(int argc, char *argv[])
 	int daddress;
 	char filename[20];
 	int pec = 0;
-	int flags = 0;
+	int opt;
 	int force = 0, yes = 0, version = 0, all_addrs = 0;
 	int length;
 	unsigned char block_data[I2C_SMBUS_BLOCK_MAX];
 
 	/* handle (optional) flags first */
-	while (1+flags < argc && argv[1+flags][0] == '-') {
-		switch (argv[1+flags][1]) {
+	while ((opt = getopt(argc, argv, "Vafy")) != -1) {
+		switch (opt) {
 		case 'V': version = 1; break;
 		case 'f': force = 1; break;
 		case 'y': yes = 1; break;
 		case 'a': all_addrs = 1; break;
-		default:
-			fprintf(stderr, "Error: Unsupported option "
-				"\"%s\"!\n", argv[1+flags]);
+		case '?':
 			help();
 			exit(1);
 		}
-		flags++;
 	}
 
 	if (version) {
@@ -206,20 +203,20 @@ int main(int argc, char *argv[])
 		exit(0);
 	}
 
-	if (argc < flags + 3)
+	if (argc < optind + 2)
 		help();
 
-	i2cbus = lookup_i2c_bus(argv[flags+1]);
+	i2cbus = lookup_i2c_bus(argv[optind]);
 	if (i2cbus < 0)
 		help();
 
-	address = parse_i2c_address(argv[flags+2], all_addrs);
+	address = parse_i2c_address(argv[optind+1], all_addrs);
 	if (address < 0)
 		help();
 
-	if (argc > flags + 3) {
+	if (argc > optind + 2) {
 		size = I2C_SMBUS_BYTE_DATA;
-		daddress = strtol(argv[flags+3], &end, 0);
+		daddress = strtol(argv[optind+2], &end, 0);
 		if (*end || daddress < 0 || daddress > 0xff) {
 			fprintf(stderr, "Error: Data address invalid!\n");
 			help();
@@ -229,8 +226,8 @@ int main(int argc, char *argv[])
 		daddress = -1;
 	}
 
-	if (argc > flags + 4) {
-		switch (argv[flags+4][0]) {
+	if (argc > optind + 3) {
+		switch (argv[optind+3][0]) {
 		case 'b': size = I2C_SMBUS_BYTE_DATA; break;
 		case 'w': size = I2C_SMBUS_WORD_DATA; break;
 		case 'c': size = I2C_SMBUS_BYTE; break;
@@ -240,19 +237,19 @@ int main(int argc, char *argv[])
 			fprintf(stderr, "Error: Invalid mode!\n");
 			help();
 		}
-		pec = argv[flags+4][1] == 'p';
+		pec = argv[optind+3][1] == 'p';
 		if (size == I2C_SMBUS_I2C_BLOCK_DATA && pec) {
 			fprintf(stderr, "Error: PEC not supported for I2C block data!\n");
 			help();
 		}
 	}
 
-	if (argc > flags + 5) {
+	if (argc > optind + 4) {
 		if (size != I2C_SMBUS_I2C_BLOCK_DATA) {
 			fprintf(stderr, "Error: Length only valid for I2C block data!\n");
 			help();
 		}
-		length = strtol(argv[flags+5], &end, 0);
+		length = strtol(argv[optind+4], &end, 0);
 		if (*end || length < 1 || length > I2C_SMBUS_BLOCK_MAX) {
 			fprintf(stderr, "Error: Length invalid!\n");
 			help();
diff --git a/tools/i2cset.c b/tools/i2cset.c
index 4a3f597..aaac372 100644
--- a/tools/i2cset.c
+++ b/tools/i2cset.c
@@ -2,7 +2,7 @@
     i2cset.c - A user-space program to write an I2C register.
     Copyright (C) 2001-2003  Frodo Looijaard <frodol@dds.nl>, and
                              Mark D. Studebaker <mdsxyz123@yahoo.com>
-    Copyright (C) 2004-2012  Jean Delvare <jdelvare@suse.de>
+    Copyright (C) 2004-2022  Jean Delvare <jdelvare@suse.de>
 
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -162,31 +162,24 @@ int main(int argc, char *argv[])
 	int value, daddress, vmask = 0;
 	char filename[20];
 	int pec = 0;
-	int flags = 0;
+	int opt;
 	int force = 0, yes = 0, version = 0, readback = 0, all_addrs = 0;
 	unsigned char block[I2C_SMBUS_BLOCK_MAX];
 	int len;
 
 	/* handle (optional) flags first */
-	while (1+flags < argc && argv[1+flags][0] == '-') {
-		switch (argv[1+flags][1]) {
+	while ((opt = getopt(argc, argv, "Vafm:ry")) != -1) {
+		switch (opt) {
 		case 'V': version = 1; break;
 		case 'f': force = 1; break;
 		case 'y': yes = 1; break;
-		case 'm':
-			if (2+flags < argc)
-				maskp = argv[2+flags];
-			flags++;
-			break;
+		case 'm': maskp = optarg; break;
 		case 'r': readback = 1; break;
 		case 'a': all_addrs = 1; break;
-		default:
-			fprintf(stderr, "Error: Unsupported option "
-				"\"%s\"!\n", argv[1+flags]);
+		case '?':
 			help();
 			exit(1);
 		}
-		flags++;
 	}
 
 	if (version) {
@@ -194,33 +187,33 @@ int main(int argc, char *argv[])
 		exit(0);
 	}
 
-	if (argc < flags + 4)
+	if (argc < optind + 3)
 		help();
 
-	i2cbus = lookup_i2c_bus(argv[flags+1]);
+	i2cbus = lookup_i2c_bus(argv[optind]);
 	if (i2cbus < 0)
 		help();
 
-	address = parse_i2c_address(argv[flags+2], all_addrs);
+	address = parse_i2c_address(argv[optind+1], all_addrs);
 	if (address < 0)
 		help();
 
-	daddress = strtol(argv[flags+3], &end, 0);
+	daddress = strtol(argv[optind+2], &end, 0);
 	if (*end || daddress < 0 || daddress > 0xff) {
 		fprintf(stderr, "Error: Data address invalid!\n");
 		help();
 	}
 
 	/* check for command/mode */
-	if (argc == flags + 4) {
+	if (argc == optind + 3) {
 		/* Implicit "c" */
 		size = I2C_SMBUS_BYTE;
-	} else if (argc == flags + 5) {
+	} else if (argc == optind + 4) {
 		/* "c", "cp",  or implicit "b" */
-		if (!strcmp(argv[flags+4], "c")
-		 || !strcmp(argv[flags+4], "cp")) {
+		if (!strcmp(argv[optind+3], "c")
+		 || !strcmp(argv[optind+3], "cp")) {
 			size = I2C_SMBUS_BYTE;
-			pec = argv[flags+4][1] == 'p';
+			pec = argv[optind+3][1] == 'p';
 		} else {
 			size = I2C_SMBUS_BYTE_DATA;
 		}
@@ -250,11 +243,11 @@ int main(int argc, char *argv[])
 				fprintf(stderr, "Error: Mask not supported for block writes!\n");
 				help();
 			}
-			if (argc > (int)sizeof(block) + flags + 5) {
+			if (argc > (int)sizeof(block) + optind + 4) {
 				fprintf(stderr, "Error: Too many arguments!\n");
 				help();
 			}
-		} else if (argc != flags + 6) {
+		} else if (argc != optind + 5) {
 			fprintf(stderr, "Error: Too many arguments!\n");
 			help();
 		}
@@ -270,7 +263,7 @@ int main(int argc, char *argv[])
 		break;
 	case I2C_SMBUS_BYTE_DATA:
 	case I2C_SMBUS_WORD_DATA:
-		value = strtol(argv[flags+4], &end, 0);
+		value = strtol(argv[optind+3], &end, 0);
 		if (*end || value < 0) {
 			fprintf(stderr, "Error: Data value invalid!\n");
 			help();
@@ -283,8 +276,8 @@ int main(int argc, char *argv[])
 		break;
 	case I2C_SMBUS_BLOCK_DATA:
 	case I2C_SMBUS_I2C_BLOCK_DATA:
-		for (len = 0; len + flags + 5 < argc; len++) {
-			value = strtol(argv[flags + len + 4], &end, 0);
+		for (len = 0; len + optind + 4 < argc; len++) {
+			value = strtol(argv[optind + len + 3], &end, 0);
 			if (*end || value < 0) {
 				fprintf(stderr, "Error: Data value invalid!\n");
 				help();
diff --git a/tools/i2ctransfer.c b/tools/i2ctransfer.c
index b0e8d43..716eac0 100644
--- a/tools/i2ctransfer.c
+++ b/tools/i2ctransfer.c
@@ -131,7 +131,7 @@ static int confirm(const char *filename, struct i2c_msg *msgs, __u32 nmsgs)
 int main(int argc, char *argv[])
 {
 	char filename[20];
-	int i2cbus, address = -1, file, arg_idx = 1, nmsgs = 0, nmsgs_sent, i;
+	int i2cbus, address = -1, file, opt, arg_idx, nmsgs = 0, nmsgs_sent, i;
 	int force = 0, yes = 0, version = 0, verbose = 0, all_addrs = 0;
 	struct i2c_msg msgs[I2C_RDRW_IOCTL_MAX_MSGS];
 	enum parse_state state = PARSE_GET_DESC;
@@ -140,21 +140,18 @@ int main(int argc, char *argv[])
 	for (i = 0; i < I2C_RDRW_IOCTL_MAX_MSGS; i++)
 		msgs[i].buf = NULL;
 
-	/* handle (optional) arg_idx first */
-	while (arg_idx < argc && argv[arg_idx][0] == '-') {
-		switch (argv[arg_idx][1]) {
+	/* handle (optional) flags first */
+	while ((opt = getopt(argc, argv, "Vafvy")) != -1) {
+		switch (opt) {
 		case 'V': version = 1; break;
 		case 'v': verbose = 1; break;
 		case 'f': force = 1; break;
 		case 'y': yes = 1; break;
 		case 'a': all_addrs = 1; break;
-		default:
-			fprintf(stderr, "Error: Unsupported option \"%s\"!\n",
-				argv[arg_idx]);
+		case '?':
 			help();
 			exit(1);
 		}
-		arg_idx++;
 	}
 
 	if (version) {
@@ -162,6 +159,7 @@ int main(int argc, char *argv[])
 		exit(0);
 	}
 
+	arg_idx = optind;
 	if (arg_idx == argc) {
 		help();
 		exit(1);