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Diffstat (limited to 'tools/include/nolibc/stdlib.h')
-rw-r--r-- | tools/include/nolibc/stdlib.h | 425 |
1 files changed, 425 insertions, 0 deletions
diff --git a/tools/include/nolibc/stdlib.h b/tools/include/nolibc/stdlib.h new file mode 100644 index 000000000..a24000d1e --- /dev/null +++ b/tools/include/nolibc/stdlib.h @@ -0,0 +1,425 @@ +/* SPDX-License-Identifier: LGPL-2.1 OR MIT */ +/* + * stdlib function definitions for NOLIBC + * Copyright (C) 2017-2021 Willy Tarreau <w@1wt.eu> + */ + +#ifndef _NOLIBC_STDLIB_H +#define _NOLIBC_STDLIB_H + +#include "std.h" +#include "arch.h" +#include "types.h" +#include "sys.h" +#include "string.h" + +struct nolibc_heap { + size_t len; + char user_p[] __attribute__((__aligned__)); +}; + +/* Buffer used to store int-to-ASCII conversions. Will only be implemented if + * any of the related functions is implemented. The area is large enough to + * store "18446744073709551615" or "-9223372036854775808" and the final zero. + */ +static __attribute__((unused)) char itoa_buffer[21]; + +/* + * As much as possible, please keep functions alphabetically sorted. + */ + +/* must be exported, as it's used by libgcc for various divide functions */ +__attribute__((weak,unused,noreturn,section(".text.nolibc_abort"))) +void abort(void) +{ + sys_kill(sys_getpid(), SIGABRT); + for (;;); +} + +static __attribute__((unused)) +long atol(const char *s) +{ + unsigned long ret = 0; + unsigned long d; + int neg = 0; + + if (*s == '-') { + neg = 1; + s++; + } + + while (1) { + d = (*s++) - '0'; + if (d > 9) + break; + ret *= 10; + ret += d; + } + + return neg ? -ret : ret; +} + +static __attribute__((unused)) +int atoi(const char *s) +{ + return atol(s); +} + +static __attribute__((unused)) +void free(void *ptr) +{ + struct nolibc_heap *heap; + + if (!ptr) + return; + + heap = container_of(ptr, struct nolibc_heap, user_p); + munmap(heap, heap->len); +} + +/* getenv() tries to find the environment variable named <name> in the + * environment array pointed to by global variable "environ" which must be + * declared as a char **, and must be terminated by a NULL (it is recommended + * to set this variable to the "envp" argument of main()). If the requested + * environment variable exists its value is returned otherwise NULL is + * returned. getenv() is forcefully inlined so that the reference to "environ" + * will be dropped if unused, even at -O0. + */ +static __attribute__((unused)) +char *_getenv(const char *name, char **environ) +{ + int idx, i; + + if (environ) { + for (idx = 0; environ[idx]; idx++) { + for (i = 0; name[i] && name[i] == environ[idx][i];) + i++; + if (!name[i] && environ[idx][i] == '=') + return &environ[idx][i+1]; + } + } + return NULL; +} + +static inline __attribute__((unused,always_inline)) +char *getenv(const char *name) +{ + extern char **environ; + return _getenv(name, environ); +} + +static __attribute__((unused)) +void *malloc(size_t len) +{ + struct nolibc_heap *heap; + + /* Always allocate memory with size multiple of 4096. */ + len = sizeof(*heap) + len; + len = (len + 4095UL) & -4096UL; + heap = mmap(NULL, len, PROT_READ|PROT_WRITE, MAP_ANONYMOUS|MAP_PRIVATE, + -1, 0); + if (__builtin_expect(heap == MAP_FAILED, 0)) + return NULL; + + heap->len = len; + return heap->user_p; +} + +static __attribute__((unused)) +void *calloc(size_t size, size_t nmemb) +{ + size_t x = size * nmemb; + + if (__builtin_expect(size && ((x / size) != nmemb), 0)) { + SET_ERRNO(ENOMEM); + return NULL; + } + + /* + * No need to zero the heap, the MAP_ANONYMOUS in malloc() + * already does it. + */ + return malloc(x); +} + +static __attribute__((unused)) +void *realloc(void *old_ptr, size_t new_size) +{ + struct nolibc_heap *heap; + size_t user_p_len; + void *ret; + + if (!old_ptr) + return malloc(new_size); + + heap = container_of(old_ptr, struct nolibc_heap, user_p); + user_p_len = heap->len - sizeof(*heap); + /* + * Don't realloc() if @user_p_len >= @new_size, this block of + * memory is still enough to handle the @new_size. Just return + * the same pointer. + */ + if (user_p_len >= new_size) + return old_ptr; + + ret = malloc(new_size); + if (__builtin_expect(!ret, 0)) + return NULL; + + memcpy(ret, heap->user_p, heap->len); + munmap(heap, heap->len); + return ret; +} + +/* Converts the unsigned long integer <in> to its hex representation into + * buffer <buffer>, which must be long enough to store the number and the + * trailing zero (17 bytes for "ffffffffffffffff" or 9 for "ffffffff"). The + * buffer is filled from the first byte, and the number of characters emitted + * (not counting the trailing zero) is returned. The function is constructed + * in a way to optimize the code size and avoid any divide that could add a + * dependency on large external functions. + */ +static __attribute__((unused)) +int utoh_r(unsigned long in, char *buffer) +{ + signed char pos = (~0UL > 0xfffffffful) ? 60 : 28; + int digits = 0; + int dig; + + do { + dig = in >> pos; + in -= (uint64_t)dig << pos; + pos -= 4; + if (dig || digits || pos < 0) { + if (dig > 9) + dig += 'a' - '0' - 10; + buffer[digits++] = '0' + dig; + } + } while (pos >= 0); + + buffer[digits] = 0; + return digits; +} + +/* converts unsigned long <in> to an hex string using the static itoa_buffer + * and returns the pointer to that string. + */ +static inline __attribute__((unused)) +char *utoh(unsigned long in) +{ + utoh_r(in, itoa_buffer); + return itoa_buffer; +} + +/* Converts the unsigned long integer <in> to its string representation into + * buffer <buffer>, which must be long enough to store the number and the + * trailing zero (21 bytes for 18446744073709551615 in 64-bit, 11 for + * 4294967295 in 32-bit). The buffer is filled from the first byte, and the + * number of characters emitted (not counting the trailing zero) is returned. + * The function is constructed in a way to optimize the code size and avoid + * any divide that could add a dependency on large external functions. + */ +static __attribute__((unused)) +int utoa_r(unsigned long in, char *buffer) +{ + unsigned long lim; + int digits = 0; + int pos = (~0UL > 0xfffffffful) ? 19 : 9; + int dig; + + do { + for (dig = 0, lim = 1; dig < pos; dig++) + lim *= 10; + + if (digits || in >= lim || !pos) { + for (dig = 0; in >= lim; dig++) + in -= lim; + buffer[digits++] = '0' + dig; + } + } while (pos--); + + buffer[digits] = 0; + return digits; +} + +/* Converts the signed long integer <in> to its string representation into + * buffer <buffer>, which must be long enough to store the number and the + * trailing zero (21 bytes for -9223372036854775808 in 64-bit, 12 for + * -2147483648 in 32-bit). The buffer is filled from the first byte, and the + * number of characters emitted (not counting the trailing zero) is returned. + */ +static __attribute__((unused)) +int itoa_r(long in, char *buffer) +{ + char *ptr = buffer; + int len = 0; + + if (in < 0) { + in = -in; + *(ptr++) = '-'; + len++; + } + len += utoa_r(in, ptr); + return len; +} + +/* for historical compatibility, same as above but returns the pointer to the + * buffer. + */ +static inline __attribute__((unused)) +char *ltoa_r(long in, char *buffer) +{ + itoa_r(in, buffer); + return buffer; +} + +/* converts long integer <in> to a string using the static itoa_buffer and + * returns the pointer to that string. + */ +static inline __attribute__((unused)) +char *itoa(long in) +{ + itoa_r(in, itoa_buffer); + return itoa_buffer; +} + +/* converts long integer <in> to a string using the static itoa_buffer and + * returns the pointer to that string. Same as above, for compatibility. + */ +static inline __attribute__((unused)) +char *ltoa(long in) +{ + itoa_r(in, itoa_buffer); + return itoa_buffer; +} + +/* converts unsigned long integer <in> to a string using the static itoa_buffer + * and returns the pointer to that string. + */ +static inline __attribute__((unused)) +char *utoa(unsigned long in) +{ + utoa_r(in, itoa_buffer); + return itoa_buffer; +} + +/* Converts the unsigned 64-bit integer <in> to its hex representation into + * buffer <buffer>, which must be long enough to store the number and the + * trailing zero (17 bytes for "ffffffffffffffff"). The buffer is filled from + * the first byte, and the number of characters emitted (not counting the + * trailing zero) is returned. The function is constructed in a way to optimize + * the code size and avoid any divide that could add a dependency on large + * external functions. + */ +static __attribute__((unused)) +int u64toh_r(uint64_t in, char *buffer) +{ + signed char pos = 60; + int digits = 0; + int dig; + + do { + if (sizeof(long) >= 8) { + dig = (in >> pos) & 0xF; + } else { + /* 32-bit platforms: avoid a 64-bit shift */ + uint32_t d = (pos >= 32) ? (in >> 32) : in; + dig = (d >> (pos & 31)) & 0xF; + } + if (dig > 9) + dig += 'a' - '0' - 10; + pos -= 4; + if (dig || digits || pos < 0) + buffer[digits++] = '0' + dig; + } while (pos >= 0); + + buffer[digits] = 0; + return digits; +} + +/* converts uint64_t <in> to an hex string using the static itoa_buffer and + * returns the pointer to that string. + */ +static inline __attribute__((unused)) +char *u64toh(uint64_t in) +{ + u64toh_r(in, itoa_buffer); + return itoa_buffer; +} + +/* Converts the unsigned 64-bit integer <in> to its string representation into + * buffer <buffer>, which must be long enough to store the number and the + * trailing zero (21 bytes for 18446744073709551615). The buffer is filled from + * the first byte, and the number of characters emitted (not counting the + * trailing zero) is returned. The function is constructed in a way to optimize + * the code size and avoid any divide that could add a dependency on large + * external functions. + */ +static __attribute__((unused)) +int u64toa_r(uint64_t in, char *buffer) +{ + unsigned long long lim; + int digits = 0; + int pos = 19; /* start with the highest possible digit */ + int dig; + + do { + for (dig = 0, lim = 1; dig < pos; dig++) + lim *= 10; + + if (digits || in >= lim || !pos) { + for (dig = 0; in >= lim; dig++) + in -= lim; + buffer[digits++] = '0' + dig; + } + } while (pos--); + + buffer[digits] = 0; + return digits; +} + +/* Converts the signed 64-bit integer <in> to its string representation into + * buffer <buffer>, which must be long enough to store the number and the + * trailing zero (21 bytes for -9223372036854775808). The buffer is filled from + * the first byte, and the number of characters emitted (not counting the + * trailing zero) is returned. + */ +static __attribute__((unused)) +int i64toa_r(int64_t in, char *buffer) +{ + char *ptr = buffer; + int len = 0; + + if (in < 0) { + in = -in; + *(ptr++) = '-'; + len++; + } + len += u64toa_r(in, ptr); + return len; +} + +/* converts int64_t <in> to a string using the static itoa_buffer and returns + * the pointer to that string. + */ +static inline __attribute__((unused)) +char *i64toa(int64_t in) +{ + i64toa_r(in, itoa_buffer); + return itoa_buffer; +} + +/* converts uint64_t <in> to a string using the static itoa_buffer and returns + * the pointer to that string. + */ +static inline __attribute__((unused)) +char *u64toa(uint64_t in) +{ + u64toa_r(in, itoa_buffer); + return itoa_buffer; +} + +/* make sure to include all global symbols */ +#include "nolibc.h" + +#endif /* _NOLIBC_STDLIB_H */ |