xref: /openbmc/linux/drivers/acpi/acpica/dbhistry.c (revision ca5999fd)
1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3  *
4  * Module Name: dbhistry - debugger HISTORY command
5  *
6  * Copyright (C) 2000 - 2020, Intel Corp.
7  *
8  *****************************************************************************/
9 
10 #include <acpi/acpi.h>
11 #include "accommon.h"
12 #include "acdebug.h"
13 
14 #define _COMPONENT          ACPI_CA_DEBUGGER
15 ACPI_MODULE_NAME("dbhistry")
16 
17 #define HI_NO_HISTORY       0
18 #define HI_RECORD_HISTORY   1
19 #define HISTORY_SIZE        40
20 typedef struct history_info {
21 	char *command;
22 	u32 cmd_num;
23 
24 } HISTORY_INFO;
25 
26 static HISTORY_INFO acpi_gbl_history_buffer[HISTORY_SIZE];
27 static u16 acpi_gbl_lo_history = 0;
28 static u16 acpi_gbl_num_history = 0;
29 static u16 acpi_gbl_next_history_index = 0;
30 
31 /*******************************************************************************
32  *
33  * FUNCTION:    acpi_db_add_to_history
34  *
35  * PARAMETERS:  command_line    - Command to add
36  *
37  * RETURN:      None
38  *
39  * DESCRIPTION: Add a command line to the history buffer.
40  *
41  ******************************************************************************/
42 
43 void acpi_db_add_to_history(char *command_line)
44 {
45 	u16 cmd_len;
46 	u16 buffer_len;
47 
48 	/* Put command into the next available slot */
49 
50 	cmd_len = (u16)strlen(command_line);
51 	if (!cmd_len) {
52 		return;
53 	}
54 
55 	if (acpi_gbl_history_buffer[acpi_gbl_next_history_index].command !=
56 	    NULL) {
57 		buffer_len =
58 		    (u16)
59 		    strlen(acpi_gbl_history_buffer[acpi_gbl_next_history_index].
60 			   command);
61 
62 		if (cmd_len > buffer_len) {
63 			acpi_os_free(acpi_gbl_history_buffer
64 				     [acpi_gbl_next_history_index].command);
65 			acpi_gbl_history_buffer[acpi_gbl_next_history_index].
66 			    command = acpi_os_allocate(cmd_len + 1);
67 		}
68 	} else {
69 		acpi_gbl_history_buffer[acpi_gbl_next_history_index].command =
70 		    acpi_os_allocate(cmd_len + 1);
71 	}
72 
73 	strcpy(acpi_gbl_history_buffer[acpi_gbl_next_history_index].command,
74 	       command_line);
75 
76 	acpi_gbl_history_buffer[acpi_gbl_next_history_index].cmd_num =
77 	    acpi_gbl_next_cmd_num;
78 
79 	/* Adjust indexes */
80 
81 	if ((acpi_gbl_num_history == HISTORY_SIZE) &&
82 	    (acpi_gbl_next_history_index == acpi_gbl_lo_history)) {
83 		acpi_gbl_lo_history++;
84 		if (acpi_gbl_lo_history >= HISTORY_SIZE) {
85 			acpi_gbl_lo_history = 0;
86 		}
87 	}
88 
89 	acpi_gbl_next_history_index++;
90 	if (acpi_gbl_next_history_index >= HISTORY_SIZE) {
91 		acpi_gbl_next_history_index = 0;
92 	}
93 
94 	acpi_gbl_next_cmd_num++;
95 	if (acpi_gbl_num_history < HISTORY_SIZE) {
96 		acpi_gbl_num_history++;
97 	}
98 }
99 
100 /*******************************************************************************
101  *
102  * FUNCTION:    acpi_db_display_history
103  *
104  * PARAMETERS:  None
105  *
106  * RETURN:      None
107  *
108  * DESCRIPTION: Display the contents of the history buffer
109  *
110  ******************************************************************************/
111 
112 void acpi_db_display_history(void)
113 {
114 	u32 i;
115 	u16 history_index;
116 
117 	history_index = acpi_gbl_lo_history;
118 
119 	/* Dump entire history buffer */
120 
121 	for (i = 0; i < acpi_gbl_num_history; i++) {
122 		if (acpi_gbl_history_buffer[history_index].command) {
123 			acpi_os_printf("%3u %s\n",
124 				       acpi_gbl_history_buffer[history_index].
125 				       cmd_num,
126 				       acpi_gbl_history_buffer[history_index].
127 				       command);
128 		}
129 
130 		history_index++;
131 		if (history_index >= HISTORY_SIZE) {
132 			history_index = 0;
133 		}
134 	}
135 }
136 
137 /*******************************************************************************
138  *
139  * FUNCTION:    acpi_db_get_from_history
140  *
141  * PARAMETERS:  command_num_arg         - String containing the number of the
142  *                                        command to be retrieved
143  *
144  * RETURN:      Pointer to the retrieved command. Null on error.
145  *
146  * DESCRIPTION: Get a command from the history buffer
147  *
148  ******************************************************************************/
149 
150 char *acpi_db_get_from_history(char *command_num_arg)
151 {
152 	u32 cmd_num;
153 
154 	if (command_num_arg == NULL) {
155 		cmd_num = acpi_gbl_next_cmd_num - 1;
156 	}
157 
158 	else {
159 		cmd_num = strtoul(command_num_arg, NULL, 0);
160 	}
161 
162 	return (acpi_db_get_history_by_index(cmd_num));
163 }
164 
165 /*******************************************************************************
166  *
167  * FUNCTION:    acpi_db_get_history_by_index
168  *
169  * PARAMETERS:  cmd_num             - Index of the desired history entry.
170  *                                    Values are 0...(acpi_gbl_next_cmd_num - 1)
171  *
172  * RETURN:      Pointer to the retrieved command. Null on error.
173  *
174  * DESCRIPTION: Get a command from the history buffer
175  *
176  ******************************************************************************/
177 
178 char *acpi_db_get_history_by_index(u32 cmd_num)
179 {
180 	u32 i;
181 	u16 history_index;
182 
183 	/* Search history buffer */
184 
185 	history_index = acpi_gbl_lo_history;
186 	for (i = 0; i < acpi_gbl_num_history; i++) {
187 		if (acpi_gbl_history_buffer[history_index].cmd_num == cmd_num) {
188 
189 			/* Found the command, return it */
190 
191 			return (acpi_gbl_history_buffer[history_index].command);
192 		}
193 
194 		/* History buffer is circular */
195 
196 		history_index++;
197 		if (history_index >= HISTORY_SIZE) {
198 			history_index = 0;
199 		}
200 	}
201 
202 	acpi_os_printf("Invalid history number: %u\n", history_index);
203 	return (NULL);
204 }
205