1 /*
2  * Copyright (c) 2013-2014, ARM Limited and Contributors. All rights reserved.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions are met:
6  *
7  * Redistributions of source code must retain the above copyright notice, this
8  * list of conditions and the following disclaimer.
9  *
10  * Redistributions in binary form must reproduce the above copyright notice,
11  * this list of conditions and the following disclaimer in the documentation
12  * and/or other materials provided with the distribution.
13  *
14  * Neither the name of ARM nor the names of its contributors may be used
15  * to endorse or promote products derived from this software without specific
16  * prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
22  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28  * POSSIBILITY OF SUCH DAMAGE.
29  */
30 
31 #include <assert.h>
32 #include <errno.h>
33 #include <semihosting.h>
34 #include <string.h>
35 
36 #ifndef SEMIHOSTING_SUPPORTED
37 #define SEMIHOSTING_SUPPORTED  1
38 #endif
39 
40 long semihosting_call(unsigned long operation,
41 			void *system_block_address);
42 
43 typedef struct {
44 	const char *file_name;
45 	unsigned long mode;
46 	size_t name_length;
47 } smh_file_open_block_t;
48 
49 typedef struct {
50 	long handle;
51 	uintptr_t buffer;
52 	size_t length;
53 } smh_file_read_write_block_t;
54 
55 typedef struct {
56 	long handle;
57 	ssize_t location;
58 } smh_file_seek_block_t;
59 
60 typedef struct {
61 	char *command_line;
62 	size_t command_length;
63 } smh_system_block_t;
64 
semihosting_connection_supported(void)65 long semihosting_connection_supported(void)
66 {
67 	return SEMIHOSTING_SUPPORTED;
68 }
69 
semihosting_file_open(const char * file_name,size_t mode)70 long semihosting_file_open(const char *file_name, size_t mode)
71 {
72 	smh_file_open_block_t open_block;
73 
74 	open_block.file_name = file_name;
75 	open_block.mode = mode;
76 	open_block.name_length = strlen(file_name);
77 
78 	return semihosting_call(SEMIHOSTING_SYS_OPEN,
79 				(void *) &open_block);
80 }
81 
semihosting_file_seek(long file_handle,ssize_t offset)82 long semihosting_file_seek(long file_handle, ssize_t offset)
83 {
84 	smh_file_seek_block_t seek_block;
85 	long result;
86 
87 	seek_block.handle = file_handle;
88 	seek_block.location = offset;
89 
90 	result = semihosting_call(SEMIHOSTING_SYS_SEEK,
91 				  (void *) &seek_block);
92 
93 	if (result)
94 		result = semihosting_call(SEMIHOSTING_SYS_ERRNO, 0);
95 
96 	return result;
97 }
98 
semihosting_file_read(long file_handle,size_t * length,uintptr_t buffer)99 long semihosting_file_read(long file_handle, size_t *length, uintptr_t buffer)
100 {
101 	smh_file_read_write_block_t read_block;
102 	long result = -EINVAL;
103 
104 	if ((length == NULL) || (buffer == (uintptr_t)NULL))
105 		return result;
106 
107 	read_block.handle = file_handle;
108 	read_block.buffer = buffer;
109 	read_block.length = *length;
110 
111 	result = semihosting_call(SEMIHOSTING_SYS_READ,
112 				  (void *) &read_block);
113 
114 	if (result == *length) {
115 		return -EINVAL;
116 	} else if (result < *length) {
117 		*length -= result;
118 		return 0;
119 	} else
120 		return result;
121 }
122 
semihosting_file_write(long file_handle,size_t * length,const uintptr_t buffer)123 long semihosting_file_write(long file_handle,
124 			    size_t *length,
125 			    const uintptr_t buffer)
126 {
127 	smh_file_read_write_block_t write_block;
128 
129 	if ((length == NULL) || (buffer == (uintptr_t)NULL))
130 		return -EINVAL;
131 
132 	write_block.handle = file_handle;
133 	write_block.buffer = (uintptr_t)buffer; /* cast away const */
134 	write_block.length = *length;
135 
136 	*length = semihosting_call(SEMIHOSTING_SYS_WRITE,
137 				   (void *) &write_block);
138 
139 	return *length;
140 }
141 
semihosting_file_close(long file_handle)142 long semihosting_file_close(long file_handle)
143 {
144 	return semihosting_call(SEMIHOSTING_SYS_CLOSE,
145 				(void *) &file_handle);
146 }
147 
semihosting_file_length(long file_handle)148 long semihosting_file_length(long file_handle)
149 {
150 	return semihosting_call(SEMIHOSTING_SYS_FLEN,
151 				(void *) &file_handle);
152 }
153 
semihosting_read_char(void)154 char semihosting_read_char(void)
155 {
156 	return semihosting_call(SEMIHOSTING_SYS_READC, NULL);
157 }
158 
semihosting_write_char(char character)159 void semihosting_write_char(char character)
160 {
161 	semihosting_call(SEMIHOSTING_SYS_WRITEC, (void *) &character);
162 }
163 
semihosting_write_string(char * string)164 void semihosting_write_string(char *string)
165 {
166 	semihosting_call(SEMIHOSTING_SYS_WRITE0, (void *) string);
167 }
168 
semihosting_system(char * command_line)169 long semihosting_system(char *command_line)
170 {
171 	smh_system_block_t system_block;
172 
173 	system_block.command_line = command_line;
174 	system_block.command_length = strlen(command_line);
175 
176 	return semihosting_call(SEMIHOSTING_SYS_SYSTEM,
177 				(void *) &system_block);
178 }
179 
semihosting_get_flen(const char * file_name)180 long semihosting_get_flen(const char *file_name)
181 {
182 	long file_handle;
183 	size_t length;
184 
185 	assert(semihosting_connection_supported());
186 
187 	file_handle = semihosting_file_open(file_name, FOPEN_MODE_RB);
188 	if (file_handle == -1)
189 		return file_handle;
190 
191 	/* Find the length of the file */
192 	length = semihosting_file_length(file_handle);
193 
194 	return semihosting_file_close(file_handle) ? -1 : length;
195 }
196 
semihosting_download_file(const char * file_name,size_t buf_size,uintptr_t buf)197 long semihosting_download_file(const char *file_name,
198 			      size_t buf_size,
199 			      uintptr_t buf)
200 {
201 	long ret = -EINVAL;
202 	size_t length;
203 	long file_handle;
204 
205 	/* Null pointer check */
206 	if (!buf)
207 		return ret;
208 
209 	assert(semihosting_connection_supported());
210 
211 	file_handle = semihosting_file_open(file_name, FOPEN_MODE_RB);
212 	if (file_handle == -1)
213 		return ret;
214 
215 	/* Find the actual length of the file */
216 	length = semihosting_file_length(file_handle);
217 	if (length == -1)
218 		goto semihosting_fail;
219 
220 	/* Signal error if we do not have enough space for the file */
221 	if (length > buf_size)
222 		goto semihosting_fail;
223 
224 	/*
225 	 * A successful read will return 0 in which case we pass back
226 	 * the actual number of bytes read. Else we pass a negative
227 	 * value indicating an error.
228 	 */
229 	ret = semihosting_file_read(file_handle, &length, buf);
230 	if (ret)
231 		goto semihosting_fail;
232 	else
233 		ret = length;
234 
235 semihosting_fail:
236 	semihosting_file_close(file_handle);
237 	return ret;
238 }
239