Add setexpr command

Add a simple expr style command that will set an env variable as the result of the command. This allows us to do simple math in shell. The following operations are supported: &, |, ^, +, -, *, /. Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

Add setexpr command
Add a simple expr style command that will set an env variable as the result of the command. This allows us to do simple math in shell. The following operations are supported: &, |, ^, +, -, *, /. Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Kumar Gala · Wolfgang Denk
1 parent 0d48926c87
Showing 3 changed files with 72 additions and 0 deletions Side-by-side Diff
common/Makefile
common/cmd_setexpr.c
include/config_cmd_all.h
@@ -88,6 +88,7 @@
 COBJS-$(CONFIG_CMD_REISER) += cmd_reiser.o
 COBJS-y += cmd_sata.o
 COBJS-$(CONFIG_CMD_SCSI) += cmd_scsi.o
+COBJS-$(CONFIG_CMD_SETEXPR) += cmd_setexpr.o
 COBJS-$(CONFIG_CMD_SPI) += cmd_spi.o
 COBJS-$(CONFIG_CMD_STRINGS) += cmd_strings.o
 COBJS-$(CONFIG_CMD_TERMINAL) += cmd_terminal.o
+/*
+ * Copyright 2008 Freescale Semiconductor, Inc.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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 the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+/*
+ * This file provides a shell like 'expr' function to return.
+ */
+
+#include <common.h>
+#include <config.h>
+#include <command.h>
+
+int do_setexpr(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
+{
+	ulong a, b;
+	char buf[16];
+
+	/* Validate arguments */
+	if ((argc != 5) || (strlen(argv[3]) != 1)) {
+		printf("Usage:\n%s\n", cmdtp->usage);
+		return 1;
+	}
+
+	a = simple_strtoul(argv[2], NULL, 16);
+	b = simple_strtoul(argv[4], NULL, 16);
+
+	switch (argv[3][0]) {
+	case '|': sprintf(buf, "%lx", (a | b)); break;
+	case '&': sprintf(buf, "%lx", (a & b)); break;
+	case '+': sprintf(buf, "%lx", (a + b)); break;
+	case '^': sprintf(buf, "%lx", (a ^ b)); break;
+	case '-': sprintf(buf, "%lx", (a - b)); break;
+	case '*': sprintf(buf, "%lx", (a * b)); break;
+	case '/': sprintf(buf, "%lx", (a / b)); break;
+	case '%': sprintf(buf, "%lx", (a % b)); break;
+	default:
+		printf("invalid op\n");
+		return 1;
+	}
+
+	setenv(argv[1], buf);
+
+	return 0;
+}
+
+U_BOOT_CMD(
+	setexpr, 5, 0, do_setexpr,
+	"setexpr - set environment variable as the result of eval expression\n",
+	"name value1 <op> value2\n"
+	"    - set environment variable 'name' to the result of the evaluated\n"
+	"      express specified by <op>.  <op> can be &, |, ^, +, -, *, /, %\n"
+);
@@ -70,6 +70,7 @@
 #define CONFIG_CMD_SAVES	/* save S record dump		*/
 #define CONFIG_CMD_SCSI		/* SCSI Support			*/
 #define CONFIG_CMD_SDRAM	/* SDRAM DIMM SPD info printout */
+#define CONFIG_CMD_SETEXPR	/* setexpr support 		*/
 #define CONFIG_CMD_SETGETDCR	/* DCR support on 4xx		*/
 #define CONFIG_CMD_SNTP		/* SNTP support			*/
 #define CONFIG_CMD_SPI		/* SPI utility			*/
...	...	@@ -88,6 +88,7 @@
88	88	COBJS-$(CONFIG_CMD_REISER) += cmd_reiser.o
89	89	COBJS-y += cmd_sata.o
90	90	COBJS-$(CONFIG_CMD_SCSI) += cmd_scsi.o
	91	+COBJS-$(CONFIG_CMD_SETEXPR) += cmd_setexpr.o
91	92	COBJS-$(CONFIG_CMD_SPI) += cmd_spi.o
92	93	COBJS-$(CONFIG_CMD_STRINGS) += cmd_strings.o
93	94	COBJS-$(CONFIG_CMD_TERMINAL) += cmd_terminal.o
	1	+/*
	2	+ * Copyright 2008 Freescale Semiconductor, Inc.
	3	+ *
	4	+ * See file CREDITS for list of people who contributed to this
	5	+ * project.
	6	+ *
	7	+ * This program is free software; you can redistribute it and/or
	8	+ * modify it under the terms of the GNU General Public License as
	9	+ * published by the Free Software Foundation; either version 2 of
	10	+ * the License, or (at your option) any later version.
	11	+ *
	12	+ * This program is distributed in the hope that it will be useful,
	13	+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	+ * GNU General Public License for more details.
	16	+ *
	17	+ * You should have received a copy of the GNU General Public License
	18	+ * along with this program; if not, write to the Free Software
	19	+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
	20	+ * MA 02111-1307 USA
	21	+ */
	22	+
	23	+/*
	24	+ * This file provides a shell like 'expr' function to return.
	25	+ */
	26	+
	27	+#include <common.h>
	28	+#include <config.h>
	29	+#include <command.h>
	30	+
	31	+int do_setexpr(cmd_tbl_t cmdtp, int flag, int argc, char argv[])
	32	+{
	33	+ ulong a, b;
	34	+ char buf[16];
	35	+
	36	+ /* Validate arguments */
	37	+ if ((argc != 5) \|\| (strlen(argv[3]) != 1)) {
	38	+ printf("Usage:\n%s\n", cmdtp->usage);
	39	+ return 1;
	40	+ }
	41	+
	42	+ a = simple_strtoul(argv[2], NULL, 16);
	43	+ b = simple_strtoul(argv[4], NULL, 16);
	44	+
	45	+ switch (argv[3][0]) {
	46	+ case '\|': sprintf(buf, "%lx", (a \| b)); break;
	47	+ case '&': sprintf(buf, "%lx", (a & b)); break;
	48	+ case '+': sprintf(buf, "%lx", (a + b)); break;
	49	+ case '^': sprintf(buf, "%lx", (a ^ b)); break;
	50	+ case '-': sprintf(buf, "%lx", (a - b)); break;
	51	+ case '': sprintf(buf, "%lx", (a b)); break;
	52	+ case '/': sprintf(buf, "%lx", (a / b)); break;
	53	+ case '%': sprintf(buf, "%lx", (a % b)); break;
	54	+ default:
	55	+ printf("invalid op\n");
	56	+ return 1;
	57	+ }
	58	+
	59	+ setenv(argv[1], buf);
	60	+
	61	+ return 0;
	62	+}
	63	+
	64	+U_BOOT_CMD(
	65	+ setexpr, 5, 0, do_setexpr,
	66	+ "setexpr - set environment variable as the result of eval expression\n",
	67	+ "name value1 <op> value2\n"
	68	+ " - set environment variable 'name' to the result of the evaluated\n"
	69	+ " express specified by <op>. <op> can be &, \|, ^, +, -, *, /, %\n"
	70	+);
...	...	@@ -70,6 +70,7 @@
70	70	#define CONFIG_CMD_SAVES /* save S record dump */
71	71	#define CONFIG_CMD_SCSI /* SCSI Support */
72	72	#define CONFIG_CMD_SDRAM /* SDRAM DIMM SPD info printout */
	73	+#define CONFIG_CMD_SETEXPR /* setexpr support */
73	74	#define CONFIG_CMD_SETGETDCR /* DCR support on 4xx */
74	75	#define CONFIG_CMD_SNTP /* SNTP support */
75	76	#define CONFIG_CMD_SPI /* SPI utility */