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 <laijs@cn.fujitsu.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 0fbd012..3543bbe 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -1058,6 +1058,448 @@
}
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 = "<NULL>";
+ 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
