From 4370aa4aa75391a5e2e06bccb0919109f725ed8e Mon Sep 17 00:00:00 2001 From: Lai Jiangshan Date: Fri, 6 Mar 2009 17:21:46 +0100 Subject: [PATCH] vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan Signed-off-by: Frederic Weisbecker Cc: Linus Torvalds LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar --- include/linux/string.h | 7 + lib/Kconfig | 3 + lib/vsprintf.c | 442 +++++++++++++++++++++++++++++++++++++++++ 3 files changed, 452 insertions(+) diff --git a/include/linux/string.h b/include/linux/string.h index d18fc198aa2..27ac31784ad 100644 --- a/include/linux/string.h +++ b/include/linux/string.h @@ -10,6 +10,7 @@ #include /* for inline */ #include /* for size_t */ #include /* for NULL */ +#include extern char *strndup_user(const char __user *, long); @@ -111,6 +112,12 @@ extern void argv_free(char **argv); extern bool sysfs_streq(const char *s1, const char *s2); +#ifdef CONFIG_BINARY_PRINTF +int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args); +int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf); +int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...) __printf(3, 4); +#endif + extern ssize_t memory_read_from_buffer(void *to, size_t count, loff_t *ppos, const void *from, size_t available); diff --git a/lib/Kconfig b/lib/Kconfig index 03c2c24b908..97d62cf091a 100644 --- a/lib/Kconfig +++ b/lib/Kconfig @@ -2,6 +2,9 @@ # Library configuration # +config BINARY_PRINTF + def_bool n + menu "Library routines" config BITREVERSE diff --git a/lib/vsprintf.c b/lib/vsprintf.c index 0fbd0121d91..3543bbe8b1b 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -1058,6 +1058,448 @@ int sprintf(char * buf, const char *fmt, ...) } EXPORT_SYMBOL(sprintf); +#ifdef CONFIG_BINARY_PRINTF +/* + * bprintf service: + * vbin_printf() - VA arguments to binary data + * bstr_printf() - Binary data to text string + */ + +/** + * vbin_printf - Parse a format string and place args' binary value in a buffer + * @bin_buf: The buffer to place args' binary value + * @size: The size of the buffer(by words(32bits), not characters) + * @fmt: The format string to use + * @args: Arguments for the format string + * + * The format follows C99 vsnprintf, except %n is ignored, and its argument + * is skiped. + * + * The return value is the number of words(32bits) which would be generated for + * the given input. + * + * NOTE: + * If the return value is greater than @size, the resulting bin_buf is NOT + * valid for bstr_printf(). + */ +int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args) +{ + char *str, *end; + int qualifier; + + str = (char *)bin_buf; + end = (char *)(bin_buf + size); + +#define save_arg(type) \ +do { \ + if (sizeof(type) == 8) { \ + unsigned long long value; \ + str = PTR_ALIGN(str, sizeof(u32)); \ + value = va_arg(args, unsigned long long); \ + if (str + sizeof(type) <= end) { \ + *(u32 *)str = *(u32 *)&value; \ + *(u32 *)(str + 4) = *((u32 *)&value + 1); \ + } \ + } else { \ + unsigned long value; \ + str = PTR_ALIGN(str, sizeof(type)); \ + value = va_arg(args, int); \ + if (str + sizeof(type) <= end) \ + *(typeof(type) *)str = (type)value; \ + } \ + str += sizeof(type); \ +} while (0) + + for (; *fmt ; ++fmt) { + if (*fmt != '%') + continue; + +repeat: + /* parse flags */ + ++fmt; /* this also skips first '%' */ + if (*fmt == '-' || *fmt == '+' || *fmt == ' ' + || *fmt == '#' || *fmt == '0') + goto repeat; + + /* parse field width */ + if (isdigit(*fmt)) + skip_atoi(&fmt); + else if (*fmt == '*') { + ++fmt; + /* it's the next argument */ + save_arg(int); + } + + /* parse the precision */ + if (*fmt == '.') { + ++fmt; + if (isdigit(*fmt)) + skip_atoi(&fmt); + else if (*fmt == '*') { + ++fmt; + /* it's the next argument */ + save_arg(int); + } + } + + /* parse the conversion qualifier */ + qualifier = -1; + if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' || + *fmt == 'Z' || *fmt == 'z' || *fmt == 't') { + qualifier = *fmt; + ++fmt; + if (qualifier == 'l' && *fmt == 'l') { + qualifier = 'L'; + ++fmt; + } + } + + /* parse format type */ + switch (*fmt) { + case 'c': + save_arg(char); + continue; + case 's': { + /* save the string argument */ + const char *save_str = va_arg(args, char *); + size_t len; + if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE + || (unsigned long)save_str < PAGE_SIZE) + save_str = ""; + len = strlen(save_str); + if (str + len + 1 < end) + memcpy(str, save_str, len + 1); + str += len + 1; + continue; + } + case 'p': + save_arg(void *); + /* skip all alphanumeric pointer suffixes */ + while (isalnum(fmt[1])) + fmt++; + continue; + case 'n': { + /* skip %n 's argument */ + void *skip_arg; + if (qualifier == 'l') + skip_arg = va_arg(args, long *); + else if (qualifier == 'Z' || qualifier == 'z') + skip_arg = va_arg(args, size_t *); + else + skip_arg = va_arg(args, int *); + continue; + } + case 'o': + case 'x': + case 'X': + case 'd': + case 'i': + case 'u': + /* save arg for case: 'o', 'x', 'X', 'd', 'i', 'u' */ + if (qualifier == 'L') + save_arg(long long); + else if (qualifier == 'l') + save_arg(unsigned long); + else if (qualifier == 'Z' || qualifier == 'z') + save_arg(size_t); + else if (qualifier == 't') + save_arg(ptrdiff_t); + else if (qualifier == 'h') + save_arg(short); + else + save_arg(int); + continue; + default: + if (!*fmt) + --fmt; + continue; + } + } +#undef save_arg + + return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf; +} +EXPORT_SYMBOL_GPL(vbin_printf); + +/** + * bstr_printf - Format a string from binary arguments and place it in a buffer + * @buf: The buffer to place the result into + * @size: The size of the buffer, including the trailing null space + * @fmt: The format string to use + * @bin_buf: Binary arguments for the format string + * + * This function like C99 vsnprintf, but the difference is that vsnprintf gets + * arguments from stack, and bstr_printf gets arguments from @bin_buf which is + * a binary buffer that generated by vbin_printf. + * + * The format follows C99 vsnprintf, but has some extensions: + * %pS output the name of a text symbol + * %pF output the name of a function pointer + * %pR output the address range in a struct resource + * %n is ignored + * + * The return value is the number of characters which would + * be generated for the given input, excluding the trailing + * '\0', as per ISO C99. If you want to have the exact + * number of characters written into @buf as return value + * (not including the trailing '\0'), use vscnprintf(). If the + * return is greater than or equal to @size, the resulting + * string is truncated. + */ +int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf) +{ + unsigned long long num; + int base; + char *str, *end, c; + const char *args = (const char *)bin_buf; + + int flags; + int field_width; + int precision; + int qualifier; + + if (unlikely((int) size < 0)) { + /* There can be only one.. */ + static char warn = 1; + WARN_ON(warn); + warn = 0; + return 0; + } + + str = buf; + end = buf + size; + +#define get_arg(type) \ +({ \ + typeof(type) value; \ + if (sizeof(type) == 8) { \ + args = PTR_ALIGN(args, sizeof(u32)); \ + *(u32 *)&value = *(u32 *)args; \ + *((u32 *)&value + 1) = *(u32 *)(args + 4); \ + } else { \ + args = PTR_ALIGN(args, sizeof(type)); \ + value = *(typeof(type) *)args; \ + } \ + args += sizeof(type); \ + value; \ +}) + + /* Make sure end is always >= buf */ + if (end < buf) { + end = ((void *)-1); + size = end - buf; + } + + for (; *fmt ; ++fmt) { + if (*fmt != '%') { + if (str < end) + *str = *fmt; + ++str; + continue; + } + + /* process flags */ + flags = 0; +repeat: + ++fmt; /* this also skips first '%' */ + switch (*fmt) { + case '-': + flags |= LEFT; + goto repeat; + case '+': + flags |= PLUS; + goto repeat; + case ' ': + flags |= SPACE; + goto repeat; + case '#': + flags |= SPECIAL; + goto repeat; + case '0': + flags |= ZEROPAD; + goto repeat; + } + + /* get field width */ + field_width = -1; + if (isdigit(*fmt)) + field_width = skip_atoi(&fmt); + else if (*fmt == '*') { + ++fmt; + /* it's the next argument */ + field_width = get_arg(int); + if (field_width < 0) { + field_width = -field_width; + flags |= LEFT; + } + } + + /* get the precision */ + precision = -1; + if (*fmt == '.') { + ++fmt; + if (isdigit(*fmt)) + precision = skip_atoi(&fmt); + else if (*fmt == '*') { + ++fmt; + /* it's the next argument */ + precision = get_arg(int); + } + if (precision < 0) + precision = 0; + } + + /* get the conversion qualifier */ + qualifier = -1; + if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' || + *fmt == 'Z' || *fmt == 'z' || *fmt == 't') { + qualifier = *fmt; + ++fmt; + if (qualifier == 'l' && *fmt == 'l') { + qualifier = 'L'; + ++fmt; + } + } + + /* default base */ + base = 10; + + switch (*fmt) { + case 'c': + if (!(flags & LEFT)) { + while (--field_width > 0) { + if (str < end) + *str = ' '; + ++str; + } + } + c = (unsigned char) get_arg(char); + if (str < end) + *str = c; + ++str; + while (--field_width > 0) { + if (str < end) + *str = ' '; + ++str; + } + continue; + + case 's':{ + const char *str_arg = args; + size_t len = strlen(str_arg); + args += len + 1; + str = string(str, end, (char *)str_arg, field_width, + precision, flags); + continue; + } + + case 'p': + str = pointer(fmt+1, str, end, get_arg(void *), + field_width, precision, flags); + /* Skip all alphanumeric pointer suffixes */ + while (isalnum(fmt[1])) + fmt++; + continue; + + case 'n': + /* skip %n */ + continue; + + case '%': + if (str < end) + *str = '%'; + ++str; + continue; + + /* integer number formats - set up the flags and "break" */ + case 'o': + base = 8; + break; + + case 'x': + flags |= SMALL; + case 'X': + base = 16; + break; + + case 'd': + case 'i': + flags |= SIGN; + case 'u': + break; + + default: + if (str < end) + *str = '%'; + ++str; + if (*fmt) { + if (str < end) + *str = *fmt; + ++str; + } else { + --fmt; + } + continue; + } + if (qualifier == 'L') + num = get_arg(long long); + else if (qualifier == 'l') { + num = get_arg(unsigned long); + if (flags & SIGN) + num = (signed long) num; + } else if (qualifier == 'Z' || qualifier == 'z') { + num = get_arg(size_t); + } else if (qualifier == 't') { + num = get_arg(ptrdiff_t); + } else if (qualifier == 'h') { + num = (unsigned short) get_arg(short); + if (flags & SIGN) + num = (signed short) num; + } else { + num = get_arg(unsigned int); + if (flags & SIGN) + num = (signed int) num; + } + str = number(str, end, num, base, + field_width, precision, flags); + } + if (size > 0) { + if (str < end) + *str = '\0'; + else + end[-1] = '\0'; + } +#undef get_arg + + /* the trailing null byte doesn't count towards the total */ + return str - buf; +} +EXPORT_SYMBOL_GPL(bstr_printf); + +/** + * bprintf - Parse a format string and place args' binary value in a buffer + * @bin_buf: The buffer to place args' binary value + * @size: The size of the buffer(by words(32bits), not characters) + * @fmt: The format string to use + * @...: Arguments for the format string + * + * The function returns the number of words(u32) written + * into @bin_buf. + */ +int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...) +{ + va_list args; + int ret; + + va_start(args, fmt); + ret = vbin_printf(bin_buf, size, fmt, args); + va_end(args); + return ret; +} +EXPORT_SYMBOL_GPL(bprintf); + +#endif /* CONFIG_BINARY_PRINTF */ + /** * vsscanf - Unformat a buffer into a list of arguments * @buf: input buffer -- 2.41.1