/* * Copyright (c) 2017-2023, Arm Limited and Contributors. All rights reserved. * * SPDX-License-Identifier: BSD-3-Clause */ #include #include #include #include #include #define get_num_va_args(_args, _lcount) \ (((_lcount) > 1) ? va_arg(_args, long long int) : \ (((_lcount) == 1) ? va_arg(_args, long int) : \ va_arg(_args, int))) #define get_unum_va_args(_args, _lcount) \ (((_lcount) > 1) ? va_arg(_args, unsigned long long int) : \ (((_lcount) == 1) ? va_arg(_args, unsigned long int) : \ va_arg(_args, unsigned int))) #define CHECK_AND_PUT_CHAR(buf, size, chars_printed, ch) \ do { \ if ((chars_printed) < (size)) { \ *(buf) = (ch); \ (buf)++; \ } \ (chars_printed)++; \ } while (false) static void string_print(char **s, size_t n, size_t *chars_printed, const char *str) { while (*str != '\0') { CHECK_AND_PUT_CHAR(*s, n, *chars_printed, *str); str++; } } static void unsigned_num_print(char **s, size_t n, size_t *chars_printed, unsigned long long int unum, unsigned int radix, char padc, int padn, bool capitalise) { /* Just need enough space to store 64 bit decimal integer */ char num_buf[20]; int i = 0; int width; unsigned int rem; char ascii_a = capitalise ? 'A' : 'a'; /* num_buf is only large enough for radix >= 10 */ if (radix < 10) { assert(0); return; } do { rem = unum % radix; if (rem < 10U) { num_buf[i] = '0' + rem; } else { num_buf[i] = ascii_a + (rem - 10U); } i++; unum /= radix; } while (unum > 0U); width = i; for (i = padn - width; i > 0; i--) { CHECK_AND_PUT_CHAR(*s, n, *chars_printed, padc); } for (i = width; i > 0; i--) { CHECK_AND_PUT_CHAR(*s, n, *chars_printed, num_buf[i - 1]); } for (i = width + padn; i < 0; i++) { CHECK_AND_PUT_CHAR(*s, n, *chars_printed, padc); } } /******************************************************************* * Reduced vsnprintf to be used for Trusted firmware. * The following type specifiers are supported: * * %x (or %X) - hexadecimal format * %d or %i - signed decimal format * %c - character format * %s - string format * %u - unsigned decimal format * %p - pointer format * * The following length specifiers are supported by this print * %l - long int * %ll - long long int * %z - size_t sized integer formats * * The following padding specifiers are supported by this print * %0NN - Left-pad the number with 0s (NN is a decimal number) * %NN - Left-pad the number or string with spaces (NN is a decimal number) * %-NN - Right-pad the number or string with spaces (NN is a decimal number) * * The function panics on all other formats specifiers. * * It returns the number of characters that would be written if the * buffer was big enough. If it returns a value lower than n, the * whole string has been written. *******************************************************************/ int vsnprintf(char *s, size_t n, const char *fmt, va_list args) { int num; unsigned long long int unum; char *str; char padc; /* Padding character */ int padn; /* Number of characters to pad */ bool left; bool capitalise; size_t chars_printed = 0U; unsigned int l_count; if (n == 0U) { /* There isn't space for anything. */ } else if (n == 1U) { /* Buffer is too small to actually write anything else. */ *s = '\0'; n = 0U; } else { /* Reserve space for the terminator character. */ n--; } while (*fmt != '\0') { left = false; padc ='\0'; padn = 0; capitalise = false; l_count = 0; if (*fmt == '%') { fmt++; /* Check the format specifier. */ loop: switch (*fmt) { case '%': CHECK_AND_PUT_CHAR(s, n, chars_printed, '%'); break; case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': padc = (*fmt == '0') ? '0' : ' '; for (padn = 0; *fmt >= '0' && *fmt <= '9'; fmt++) { padn = (padn * 10) + (*fmt - '0'); } if (left) { padn = -padn; } goto loop; case '-': left = true; fmt++; goto loop; case 'i': case 'd': num = get_num_va_args(args, l_count); if (num < 0) { CHECK_AND_PUT_CHAR(s, n, chars_printed, '-'); unum = (unsigned int)-num; } else { unum = (unsigned int)num; } unsigned_num_print(&s, n, &chars_printed, unum, 10, padc, padn, false); break; case 'c': CHECK_AND_PUT_CHAR(s, n, chars_printed, va_arg(args, int)); break; case 's': str = va_arg(args, char *); string_print(&s, n, &chars_printed, str); break; case 'u': unum = get_unum_va_args(args, l_count); unsigned_num_print(&s, n, &chars_printed, unum, 10, padc, padn, false); break; case 'z': l_count = 1; fmt++; goto loop; case 'l': l_count++; fmt++; goto loop; case 'p': unum = (uintptr_t)va_arg(args, void *); if (unum > 0U) { string_print(&s, n, &chars_printed, "0x"); padn -= 2; } unsigned_num_print(&s, n, &chars_printed, unum, 16, padc, padn, false); break; case 'X': capitalise = true; case 'x': unum = get_unum_va_args(args, l_count); unsigned_num_print(&s, n, &chars_printed, unum, 16, padc, padn, capitalise); break; default: CHECK_AND_PUT_CHAR(s, n, chars_printed, '%'); CHECK_AND_PUT_CHAR(s, n, chars_printed, *fmt); } fmt++; continue; } CHECK_AND_PUT_CHAR(s, n, chars_printed, *fmt); fmt++; } if (n > 0U) { *s = '\0'; } return (int)chars_printed; } /******************************************************************* * Reduced snprintf to be used for Trusted firmware. * The following type specifiers are supported: * * %x (or %X) - hexadecimal format * %d or %i - signed decimal format * %s - string format * %u - unsigned decimal format * %p - pointer format * * The following padding specifiers are supported by this print * %0NN - Left-pad the number with 0s (NN is a decimal number) * %NN - Left-pad the number or string with spaces (NN is a decimal number) * %-NN - Right-pad the number or string with spaces (NN is a decimal number) * * The function panics on all other formats specifiers. * * It returns the number of characters that would be written if the * buffer was big enough. If it returns a value lower than n, the * whole string has been written. *******************************************************************/ int snprintf(char *s, size_t n, const char *fmt, ...) { int count; va_list all_args; va_start(all_args, fmt); count = vsnprintf(s, n, fmt, all_args); va_end(all_args); return count; }