util/cutils: Rewrite documentation of qemu_strtol() & friends

[mirror_qemu.git] / include / qemu / cutils.h

#ifndef QEMU_CUTILS_H
#define QEMU_CUTILS_H

#include "qemu/fprintf-fn.h"

/**
 * pstrcpy:
 * @buf: buffer to copy string into
 * @buf_size: size of @buf in bytes
 * @str: string to copy
 *
 * Copy @str into @buf, including the trailing NUL, but do not
 * write more than @buf_size bytes. The resulting buffer is
 * always NUL terminated (even if the source string was too long).
 * If @buf_size is zero or negative then no bytes are copied.
 *
 * This function is similar to strncpy(), but avoids two of that
 * function's problems:
 *  * if @str fits in the buffer, pstrcpy() does not zero-fill the
 *    remaining space at the end of @buf
 *  * if @str is too long, pstrcpy() will copy the first @buf_size-1
 *    bytes and then add a NUL
 */
void pstrcpy(char *buf, int buf_size, const char *str);
/**
 * strpadcpy:
 * @buf: buffer to copy string into
 * @buf_size: size of @buf in bytes
 * @str: string to copy
 * @pad: character to pad the remainder of @buf with
 *
 * Copy @str into @buf (but *not* its trailing NUL!), and then pad the
 * rest of the buffer with the @pad character. If @str is too large
 * for the buffer then it is truncated, so that @buf contains the
 * first @buf_size characters of @str, with no terminator.
 */
void strpadcpy(char *buf, int buf_size, const char *str, char pad);
/**
 * pstrcat:
 * @buf: buffer containing existing string
 * @buf_size: size of @buf in bytes
 * @s: string to concatenate to @buf
 *
 * Append a copy of @s to the string already in @buf, but do not
 * allow the buffer to overflow. If the existing contents of @buf
 * plus @str would total more than @buf_size bytes, then write
 * as much of @str as will fit followed by a NUL terminator.
 *
 * @buf must already contain a NUL-terminated string, or the
 * behaviour is undefined.
 *
 * Returns: @buf.
 */
char *pstrcat(char *buf, int buf_size, const char *s);
/**
 * strstart:
 * @str: string to test
 * @val: prefix string to look for
 * @ptr: NULL, or pointer to be written to indicate start of
 *       the remainder of the string
 *
 * Test whether @str starts with the prefix @val.
 * If it does (including the degenerate case where @str and @val
 * are equal) then return true. If @ptr is not NULL then a
 * pointer to the first character following the prefix is written
 * to it. If @val is not a prefix of @str then return false (and
 * @ptr is not written to).
 *
 * Returns: true if @str starts with prefix @val, false otherwise.
 */
int strstart(const char *str, const char *val, const char **ptr);
/**
 * stristart:
 * @str: string to test
 * @val: prefix string to look for
 * @ptr: NULL, or pointer to be written to indicate start of
 *       the remainder of the string
 *
 * Test whether @str starts with the case-insensitive prefix @val.
 * This function behaves identically to strstart(), except that the
 * comparison is made after calling qemu_toupper() on each pair of
 * characters.
 *
 * Returns: true if @str starts with case-insensitive prefix @val,
 *          false otherwise.
 */
int stristart(const char *str, const char *val, const char **ptr);
/**
 * qemu_strnlen:
 * @s: string
 * @max_len: maximum number of bytes in @s to scan
 *
 * Return the length of the string @s, like strlen(), but do not
 * examine more than @max_len bytes of the memory pointed to by @s.
 * If no NUL terminator is found within @max_len bytes, then return
 * @max_len instead.
 *
 * This function has the same behaviour as the POSIX strnlen()
 * function.
 *
 * Returns: length of @s in bytes, or @max_len, whichever is smaller.
 */
int qemu_strnlen(const char *s, int max_len);
/**
 * qemu_strsep:
 * @input: pointer to string to parse
 * @delim: string containing delimiter characters to search for
 *
 * Locate the first occurrence of any character in @delim within
 * the string referenced by @input, and replace it with a NUL.
 * The location of the next character after the delimiter character
 * is stored into @input.
 * If the end of the string was reached without finding a delimiter
 * character, then NULL is stored into @input.
 * If @input points to a NULL pointer on entry, return NULL.
 * The return value is always the original value of *@input (and
 * so now points to a NUL-terminated string corresponding to the
 * part of the input up to the first delimiter).
 *
 * This function has the same behaviour as the BSD strsep() function.
 *
 * Returns: the pointer originally in @input.
 */
char *qemu_strsep(char **input, const char *delim);
time_t mktimegm(struct tm *tm);
int qemu_fdatasync(int fd);
int fcntl_setfl(int fd, int flag);
int qemu_parse_fd(const char *param);
int qemu_strtol(const char *nptr, const char **endptr, int base,
                long *result);
int qemu_strtoul(const char *nptr, const char **endptr, int base,
                 unsigned long *result);
int qemu_strtoll(const char *nptr, const char **endptr, int base,
                 int64_t *result);
int qemu_strtoull(const char *nptr, const char **endptr, int base,
                  uint64_t *result);

int parse_uint(const char *s, unsigned long long *value, char **endptr,
               int base);
int parse_uint_full(const char *s, unsigned long long *value, int base);

/*
 * qemu_strtosz() suffixes used to specify the default treatment of an
 * argument passed to qemu_strtosz() without an explicit suffix.
 * These should be defined using upper case characters in the range
 * A-Z, as qemu_strtosz() will use qemu_toupper() on the given argument
 * prior to comparison.
 */
#define QEMU_STRTOSZ_DEFSUFFIX_EB 'E'
#define QEMU_STRTOSZ_DEFSUFFIX_PB 'P'
#define QEMU_STRTOSZ_DEFSUFFIX_TB 'T'
#define QEMU_STRTOSZ_DEFSUFFIX_GB 'G'
#define QEMU_STRTOSZ_DEFSUFFIX_MB 'M'
#define QEMU_STRTOSZ_DEFSUFFIX_KB 'K'
#define QEMU_STRTOSZ_DEFSUFFIX_B 'B'
int64_t qemu_strtosz(const char *nptr, char **end);
int64_t qemu_strtosz_suffix(const char *nptr, char **end,
                            const char default_suffix);
int64_t qemu_strtosz_suffix_unit(const char *nptr, char **end,
                            const char default_suffix, int64_t unit);
#define K_BYTE     (1ULL << 10)
#define M_BYTE     (1ULL << 20)
#define G_BYTE     (1ULL << 30)
#define T_BYTE     (1ULL << 40)
#define P_BYTE     (1ULL << 50)
#define E_BYTE     (1ULL << 60)

/* used to print char* safely */
#define STR_OR_NULL(str) ((str) ? (str) : "null")

bool buffer_is_zero(const void *buf, size_t len);
bool test_buffer_is_zero_next_accel(void);

/*
 * Implementation of ULEB128 (http://en.wikipedia.org/wiki/LEB128)
 * Input is limited to 14-bit numbers
 */

int uleb128_encode_small(uint8_t *out, uint32_t n);
int uleb128_decode_small(const uint8_t *in, uint32_t *n);

#endif