1 /*
2  * Copyright (c) 2014-2023, Arm Limited and Contributors. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <assert.h>
8 #include <stdarg.h>
9 #include <stdbool.h>
10 #include <stddef.h>
11 #include <stdint.h>
12 #include <stdio.h>
13 
14 #define get_num_va_args(_args, _lcount)				\
15 	(((_lcount) > 1)  ? va_arg(_args, long long int) :	\
16 	(((_lcount) == 1) ? va_arg(_args, long int) :		\
17 			    va_arg(_args, int)))
18 
19 #define get_unum_va_args(_args, _lcount)				\
20 	(((_lcount) > 1)  ? va_arg(_args, unsigned long long int) :	\
21 	(((_lcount) == 1) ? va_arg(_args, unsigned long int) :		\
22 			    va_arg(_args, unsigned int)))
23 
string_print(const char * str)24 static int string_print(const char *str)
25 {
26 	int count = 0;
27 
28 	assert(str != NULL);
29 
30 	for ( ; *str != '\0'; str++) {
31 		(void)putchar(*str);
32 		count++;
33 	}
34 
35 	return count;
36 }
37 
unsigned_num_print(unsigned long long int unum,unsigned int radix,char padc,int padn,bool uppercase)38 static int unsigned_num_print(unsigned long long int unum, unsigned int radix,
39 			      char padc, int padn, bool uppercase)
40 {
41 	/* Just need enough space to store 64 bit decimal integer */
42 	char num_buf[20];
43 	int i = 0, count = 0;
44 	unsigned int rem;
45 
46 	/* num_buf is only large enough for radix >= 10 */
47 	if (radix < 10) {
48 		assert(0);
49 		return 0;
50 	}
51 
52 	do {
53 		rem = unum % radix;
54 		if (rem < 0xa) {
55 			num_buf[i] = '0' + rem;
56 		} else if (uppercase) {
57 			num_buf[i] = 'A' + (rem - 0xa);
58 		} else {
59 			num_buf[i] = 'a' + (rem - 0xa);
60 		}
61 		i++;
62 		unum /= radix;
63 	} while (unum > 0U);
64 
65 	if (padn > 0) {
66 		while (i < padn) {
67 			(void)putchar(padc);
68 			count++;
69 			padn--;
70 		}
71 	}
72 
73 	while (--i >= 0) {
74 		(void)putchar(num_buf[i]);
75 		count++;
76 	}
77 
78 	return count;
79 }
80 
81 /*******************************************************************
82  * Reduced format print for Trusted firmware.
83  * The following type specifiers are supported by this print
84  * %x - hexadecimal format
85  * %s - string format
86  * %d or %i - signed decimal format
87  * %c - character format
88  * %u - unsigned decimal format
89  * %p - pointer format
90  *
91  * The following length specifiers are supported by this print
92  * %l - long int (64-bit on AArch64)
93  * %ll - long long int (64-bit on AArch64)
94  * %z - size_t sized integer formats (64 bit on AArch64)
95  *
96  * The following padding specifiers are supported by this print
97  * %0NN - Left-pad the number with 0s (NN is a decimal number)
98  * %NN - Left-pad the number with spaces (NN is a decimal number)
99  *
100  * The print exits on all other formats specifiers other than valid
101  * combinations of the above specifiers.
102  *******************************************************************/
vprintf(const char * fmt,va_list args)103 int vprintf(const char *fmt, va_list args)
104 {
105 	int l_count;
106 	long long int num;
107 	unsigned long long int unum;
108 	char *str;
109 	char padc = '\0'; /* Padding character */
110 	int padn; /* Number of characters to pad */
111 	int count = 0; /* Number of printed characters */
112 	bool uppercase; /* Print characters in uppercase */
113 
114 	while (*fmt != '\0') {
115 		uppercase = false;
116 		l_count = 0;
117 		padn = 0;
118 
119 		if (*fmt == '%') {
120 			fmt++;
121 			/* Check the format specifier */
122 loop:
123 			switch (*fmt) {
124 			case '%':
125 				(void)putchar('%');
126 				break;
127 			case 'i': /* Fall through to next one */
128 			case 'd':
129 				num = get_num_va_args(args, l_count);
130 				if (num < 0) {
131 					(void)putchar('-');
132 					unum = (unsigned long long int)-num;
133 					padn--;
134 				} else
135 					unum = (unsigned long long int)num;
136 
137 				count += unsigned_num_print(unum, 10,
138 							    padc, padn, uppercase);
139 				break;
140 			case 'c':
141 				(void)putchar(va_arg(args, int));
142 				count++;
143 				break;
144 			case 's':
145 				str = va_arg(args, char *);
146 				count += string_print(str);
147 				break;
148 			case 'p':
149 				unum = (uintptr_t)va_arg(args, void *);
150 				if (unum > 0U) {
151 					count += string_print("0x");
152 					padn -= 2;
153 				}
154 
155 				count += unsigned_num_print(unum, 16,
156 							    padc, padn, uppercase);
157 				break;
158 			case 'X':
159 				uppercase = true;
160 				// fall through
161 			case 'x':
162 				unum = get_unum_va_args(args, l_count);
163 				count += unsigned_num_print(unum, 16,
164 							    padc, padn, uppercase);
165 				break;
166 			case 'z':
167 				if (sizeof(size_t) == 8U)
168 					l_count = 2;
169 
170 				fmt++;
171 				goto loop;
172 			case 'l':
173 				l_count++;
174 				fmt++;
175 				goto loop;
176 			case 'u':
177 				unum = get_unum_va_args(args, l_count);
178 				count += unsigned_num_print(unum, 10,
179 							    padc, padn, uppercase);
180 				break;
181 			case '0':
182 				padc = '0';
183 				padn = 0;
184 				fmt++;
185 
186 				for (;;) {
187 					char ch = *fmt;
188 					if ((ch < '0') || (ch > '9')) {
189 						goto loop;
190 					}
191 					padn = (padn * 10) + (ch - '0');
192 					fmt++;
193 				}
194 				assert(0); /* Unreachable */
195 			case '1':
196 			case '2':
197 			case '3':
198 			case '4':
199 			case '5':
200 			case '6':
201 			case '7':
202 			case '8':
203 			case '9':
204 				padc = ' ';
205 				padn = 0;
206 
207 				for (;;) {
208 					char ch = *fmt;
209 					if ((ch < '0') || (ch > '9')) {
210 						goto loop;
211 					}
212 					padn = (padn * 10) + (ch - '0');
213 					fmt++;
214 				}
215 				assert(0); /* Unreachable */
216 			default:
217 				/* Exit on any other format specifier */
218 				return -1;
219 			}
220 			fmt++;
221 			continue;
222 		}
223 		(void)putchar(*fmt);
224 		fmt++;
225 		count++;
226 	}
227 
228 	return count;
229 }
230 
printf(const char * fmt,...)231 int printf(const char *fmt, ...)
232 {
233 	int count;
234 	va_list va;
235 
236 	va_start(va, fmt);
237 	count = vprintf(fmt, va);
238 	va_end(va);
239 
240 	return count;
241 }
242