diff options
Diffstat (limited to 'linker/linker_format.c')
-rw-r--r-- | linker/linker_format.c | 703 |
1 files changed, 703 insertions, 0 deletions
diff --git a/linker/linker_format.c b/linker/linker_format.c new file mode 100644 index 0000000..4d00bd9 --- /dev/null +++ b/linker/linker_format.c @@ -0,0 +1,703 @@ +/* + * Copyright (C) 2010 The Android Open Source Project + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE + * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, + * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS + * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED + * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, + * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT + * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include <stdarg.h> +#include <string.h> +#include <errno.h> +#include <unistd.h> +#include <stdint.h> +#include <stddef.h> +#include "linker_format.h" +#include "linker_debug.h" + +/* define UNIT_TESTS to build this file as a single executable that runs + * the formatter's unit tests + */ +#define xxUNIT_TESTS + +/*** Generic output sink + ***/ + +typedef struct { + void *opaque; + void (*send)(void *opaque, const char *data, int len); +} Out; + +static void +out_send(Out *o, const void *data, size_t len) +{ + o->send(o->opaque, data, (int)len); +} + +static void +out_send_repeat(Out *o, char ch, int count) +{ + char pad[8]; + const int padSize = (int)sizeof(pad); + + memset(pad, ch, sizeof(pad)); + while (count > 0) { + int avail = count; + if (avail > padSize) { + avail = padSize; + } + o->send(o->opaque, pad, avail); + count -= avail; + } +} + +/* forward declaration */ +static void +out_vformat(Out *o, const char *format, va_list args); + +/*** Bounded buffer output + ***/ + +typedef struct { + Out out[1]; + char *buffer; + char *pos; + char *end; + int total; +} BufOut; + +static void +buf_out_send(void *opaque, const char *data, int len) +{ + BufOut *bo = opaque; + + if (len < 0) + len = strlen(data); + + bo->total += len; + + while (len > 0) { + int avail = bo->end - bo->pos; + if (avail == 0) + break; + if (avail > len) + avail = len; + memcpy(bo->pos, data, avail); + bo->pos += avail; + bo->pos[0] = '\0'; + len -= avail; + } +} + +static Out* +buf_out_init(BufOut *bo, char *buffer, size_t size) +{ + if (size == 0) + return NULL; + + bo->out->opaque = bo; + bo->out->send = buf_out_send; + bo->buffer = buffer; + bo->end = buffer + size - 1; + bo->pos = bo->buffer; + bo->pos[0] = '\0'; + bo->total = 0; + + return bo->out; +} + +static int +buf_out_length(BufOut *bo) +{ + return bo->total; +} + +static int +vformat_buffer(char *buff, size_t buffsize, const char *format, va_list args) +{ + BufOut bo; + Out *out; + + out = buf_out_init(&bo, buff, buffsize); + if (out == NULL) + return 0; + + out_vformat(out, format, args); + + return buf_out_length(&bo); +} + +int +format_buffer(char *buff, size_t buffsize, const char *format, ...) +{ + va_list args; + int ret; + + va_start(args, format); + ret = vformat_buffer(buff, buffsize, format, args); + va_end(args); + + return ret; +} + +/* The __stack_chk_fail() function calls __libc_android_log_print() + * which calls vsnprintf(). + * + * We define our version of the function here to avoid dragging + * about 25 KB of C library routines related to formatting. + */ +int +vsnprintf(char *buff, size_t bufsize, const char *format, va_list args) +{ + return format_buffer(buff, bufsize, format, args); +} + +#if LINKER_DEBUG + +#if !LINKER_DEBUG_TO_LOG + +/*** File descriptor output + ***/ + +typedef struct { + Out out[1]; + int fd; + int total; +} FdOut; + +static void +fd_out_send(void *opaque, const char *data, int len) +{ + FdOut *fdo = opaque; + + if (len < 0) + len = strlen(data); + + while (len > 0) { + int ret = write(fdo->fd, data, len); + if (ret < 0) { + if (errno == EINTR) + continue; + break; + } + data += ret; + len -= ret; + fdo->total += ret; + } +} + +static Out* +fd_out_init(FdOut *fdo, int fd) +{ + fdo->out->opaque = fdo; + fdo->out->send = fd_out_send; + fdo->fd = fd; + fdo->total = 0; + + return fdo->out; +} + +static int +fd_out_length(FdOut *fdo) +{ + return fdo->total; +} + + +int +format_fd(int fd, const char *format, ...) +{ + FdOut fdo; + Out* out; + va_list args; + + out = fd_out_init(&fdo, fd); + if (out == NULL) + return 0; + + va_start(args, format); + out_vformat(out, format, args); + va_end(args); + + return fd_out_length(&fdo); +} + +#else /* LINKER_DEBUG_TO_LOG */ + +/*** Log output + ***/ + +/* We need our own version of __libc_android_log_vprint, otherwise + * the log output is completely broken. Probably due to the fact + * that the C library is not initialized yet. + * + * You can test that by setting CUSTOM_LOG_VPRINT to 0 + */ +#define CUSTOM_LOG_VPRINT 1 + +#if CUSTOM_LOG_VPRINT + +#include <unistd.h> +#include <fcntl.h> +#include <sys/uio.h> + +static int log_vprint(int prio, const char *tag, const char *fmt, va_list args) +{ + char buf[1024]; + int result; + static int log_fd = -1; + + result = vformat_buffer(buf, sizeof buf, fmt, args); + + if (log_fd < 0) { + log_fd = open("/dev/log/main", O_WRONLY); + if (log_fd < 0) + return result; + } + + { + ssize_t ret; + struct iovec vec[3]; + + vec[0].iov_base = (unsigned char *) &prio; + vec[0].iov_len = 1; + vec[1].iov_base = (void *) tag; + vec[1].iov_len = strlen(tag) + 1; + vec[2].iov_base = (void *) buf; + vec[2].iov_len = strlen(buf) + 1; + + do { + ret = writev(log_fd, vec, 3); + } while ((ret < 0) && (errno == EINTR)); + } + return result; +} + +#define __libc_android_log_vprint log_vprint + +#else /* !CUSTOM_LOG_VPRINT */ + +extern int __libc_android_log_vprint(int prio, const char* tag, const char* format, va_list ap); + +#endif /* !CUSTOM_LOG_VPRINT */ + +int +format_log(int prio, const char *tag, const char *format, ...) +{ + int ret; + va_list args; + va_start(args, format); + ret = __libc_android_log_vprint(prio, tag, format, args); + va_end(args); + return ret; +} + +#endif /* LINKER_DEBUG_TO_LOG */ + +#endif /* LINKER_DEBUG */ + +/*** formatted output implementation + ***/ + +/* Parse a decimal string from 'format + *ppos', + * return the value, and writes the new position past + * the decimal string in '*ppos' on exit. + * + * NOTE: Does *not* handle a sign prefix. + */ +static unsigned +parse_decimal(const char *format, int *ppos) +{ + const char* p = format + *ppos; + unsigned result = 0; + + for (;;) { + int ch = *p; + unsigned d = (unsigned)(ch - '0'); + + if (d >= 10U) + break; + + result = result*10 + d; + p++; + } + *ppos = p - format; + return result; +} + +/* write an octal/decimal/number into a bounded buffer. + * assumes that bufsize > 0, and 'digits' is a string of + * digits of at least 'base' values. + */ +static void +format_number(char *buffer, size_t bufsize, uint64_t value, int base, const char *digits) +{ + char *pos = buffer; + char *end = buffer + bufsize - 1; + + /* generate digit string in reverse order */ + while (value) { + unsigned d = value % base; + value /= base; + if (pos < end) { + *pos++ = digits[d]; + } + } + + /* special case for 0 */ + if (pos == buffer) { + if (pos < end) { + *pos++ = '0'; + } + } + pos[0] = '\0'; + + /* now reverse digit string in-place */ + end = pos - 1; + pos = buffer; + while (pos < end) { + int ch = pos[0]; + pos[0] = end[0]; + end[0] = (char) ch; + pos++; + end--; + } +} + +/* Write an integer (octal or decimal) into a buffer, assumes buffsize > 2 */ +static void +format_integer(char *buffer, size_t buffsize, uint64_t value, int base, int isSigned) +{ + if (isSigned && (int64_t)value < 0) { + buffer[0] = '-'; + buffer += 1; + buffsize -= 1; + value = (uint64_t)(-(int64_t)value); + } + + format_number(buffer, buffsize, value, base, "0123456789"); +} + +/* Write an octal into a buffer, assumes buffsize > 2 */ +static void +format_octal(char *buffer, size_t buffsize, uint64_t value, int isSigned) +{ + format_integer(buffer, buffsize, value, 8, isSigned); +} + +/* Write a decimal into a buffer, assumes buffsize > 2 */ +static void +format_decimal(char *buffer, size_t buffsize, uint64_t value, int isSigned) +{ + format_integer(buffer, buffsize, value, 10, isSigned); +} + +/* Write an hexadecimal into a buffer, isCap is true for capital alphas. + * Assumes bufsize > 2 */ +static void +format_hex(char *buffer, size_t buffsize, uint64_t value, int isCap) +{ + const char *digits = isCap ? "0123456789ABCDEF" : "0123456789abcdef"; + + format_number(buffer, buffsize, value, 16, digits); +} + + +/* Perform formatted output to an output target 'o' */ +static void +out_vformat(Out *o, const char *format, va_list args) +{ + int nn = 0, mm; + int padZero = 0; + int padLeft = 0; + char sign = '\0'; + int width = -1; + int prec = -1; + size_t bytelen = sizeof(int); + const char* str; + int slen; + char buffer[32]; /* temporary buffer used to format numbers */ + + for (;;) { + char c; + + /* first, find all characters that are not 0 or '%' */ + /* then send them to the output directly */ + mm = nn; + do { + c = format[mm]; + if (c == '\0' || c == '%') + break; + mm++; + } while (1); + + if (mm > nn) { + out_send(o, format+nn, mm-nn); + nn = mm; + } + + /* is this it ? then exit */ + if (c == '\0') + break; + + /* nope, we are at a '%' modifier */ + nn++; // skip it + + /* parse flags */ + for (;;) { + c = format[nn++]; + if (c == '\0') { /* single trailing '%' ? */ + c = '%'; + out_send(o, &c, 1); + return; + } + else if (c == '0') { + padZero = 1; + continue; + } + else if (c == '-') { + padLeft = 1; + continue; + } + else if (c == ' ' || c == '+') { + sign = c; + continue; + } + break; + } + + /* parse field width */ + if ((c >= '0' && c <= '9')) { + nn --; + width = (int)parse_decimal(format, &nn); + c = format[nn++]; + } + + /* parse precision */ + if (c == '.') { + prec = (int)parse_decimal(format, &nn); + c = format[nn++]; + } + + /* length modifier */ + switch (c) { + case 'h': + bytelen = sizeof(short); + if (format[nn] == 'h') { + bytelen = sizeof(char); + nn += 1; + } + c = format[nn++]; + break; + case 'l': + bytelen = sizeof(long); + if (format[nn] == 'l') { + bytelen = sizeof(long long); + nn += 1; + } + c = format[nn++]; + break; + case 'z': + bytelen = sizeof(size_t); + c = format[nn++]; + break; + case 't': + bytelen = sizeof(ptrdiff_t); + c = format[nn++]; + break; + case 'p': + bytelen = sizeof(void*); + c = format[nn++]; + default: + ; + } + + /* conversion specifier */ + if (c == 's') { + /* string */ + str = va_arg(args, const char*); + } else if (c == 'c') { + /* character */ + /* NOTE: char is promoted to int when passed through the stack */ + buffer[0] = (char) va_arg(args, int); + buffer[1] = '\0'; + str = buffer; + } else if (c == 'p') { + uint64_t value = (uint64_t)(ptrdiff_t) va_arg(args, void*); + buffer[0] = '0'; + buffer[1] = 'x'; + format_hex(buffer + 2, sizeof buffer-2, value, 0); + str = buffer; + } else { + /* integers - first read value from stack */ + uint64_t value; + int isSigned = (c == 'd' || c == 'i' || c == 'o'); + + /* NOTE: int8_t and int16_t are promoted to int when passed + * through the stack + */ + switch (bytelen) { + case 1: value = (uint8_t) va_arg(args, int); break; + case 2: value = (uint16_t) va_arg(args, int); break; + case 4: value = va_arg(args, uint32_t); break; + case 8: value = va_arg(args, uint64_t); break; + default: return; /* should not happen */ + } + + /* sign extension, if needed */ + if (isSigned) { + int shift = 64 - 8*bytelen; + value = (uint64_t)(((int64_t)(value << shift)) >> shift); + } + + /* format the number properly into our buffer */ + switch (c) { + case 'i': case 'd': + format_integer(buffer, sizeof buffer, value, 10, isSigned); + break; + case 'o': + format_integer(buffer, sizeof buffer, value, 8, isSigned); + break; + case 'x': case 'X': + format_hex(buffer, sizeof buffer, value, (c == 'X')); + break; + default: + buffer[0] = '\0'; + } + /* then point to it */ + str = buffer; + } + + /* if we are here, 'str' points to the content that must be + * outputted. handle padding and alignment now */ + + slen = strlen(str); + + if (slen < width && !padLeft) { + char padChar = padZero ? '0' : ' '; + out_send_repeat(o, padChar, width - slen); + } + + out_send(o, str, slen); + + if (slen < width && padLeft) { + char padChar = padZero ? '0' : ' '; + out_send_repeat(o, padChar, width - slen); + } + } +} + + +#ifdef UNIT_TESTS + +#include <stdio.h> + +static int gFails = 0; + +#define MARGIN 40 + +#define UTEST_CHECK(condition,message) \ + printf("Checking %-*s: ", MARGIN, message); fflush(stdout); \ + if (!(condition)) { \ + printf("KO\n"); \ + gFails += 1; \ + } else { \ + printf("ok\n"); \ + } + +static void +utest_BufOut(void) +{ + char buffer[16]; + BufOut bo[1]; + Out* out; + int ret; + + buffer[0] = '1'; + out = buf_out_init(bo, buffer, sizeof buffer); + UTEST_CHECK(buffer[0] == '\0', "buf_out_init clears initial byte"); + out_send(out, "abc", 3); + UTEST_CHECK(!memcmp(buffer, "abc", 4), "out_send() works with BufOut"); + out_send_repeat(out, 'X', 4); + UTEST_CHECK(!memcmp(buffer, "abcXXXX", 8), "out_send_repeat() works with BufOut"); + buffer[sizeof buffer-1] = 'x'; + out_send_repeat(out, 'Y', 2*sizeof(buffer)); + UTEST_CHECK(buffer[sizeof buffer-1] == '\0', "overflows always zero-terminates"); + + out = buf_out_init(bo, buffer, sizeof buffer); + out_send_repeat(out, 'X', 2*sizeof(buffer)); + ret = buf_out_length(bo); + UTEST_CHECK(ret == 2*sizeof(buffer), "correct size returned on overflow"); +} + +static void +utest_expect(const char* result, const char* format, ...) +{ + va_list args; + BufOut bo[1]; + char buffer[256]; + Out* out = buf_out_init(bo, buffer, sizeof buffer); + + printf("Checking %-*s: ", MARGIN, format); fflush(stdout); + va_start(args, format); + out_vformat(out, format, args); + va_end(args); + + if (strcmp(result, buffer)) { + printf("KO. got '%s' expecting '%s'\n", buffer, result); + gFails += 1; + } else { + printf("ok. got '%s'\n", result); + } +} + +int main(void) +{ + utest_BufOut(); + utest_expect("", ""); + utest_expect("a", "a"); + utest_expect("01234", "01234", ""); + utest_expect("01234", "%s", "01234"); + utest_expect("aabbcc", "aa%scc", "bb"); + utest_expect("a", "%c", 'a'); + utest_expect("1234", "%d", 1234); + utest_expect("-8123", "%d", -8123); + utest_expect("16", "%hd", 0x7fff0010); + utest_expect("16", "%hhd", 0x7fffff10); + utest_expect("68719476736", "%lld", 0x1000000000); + utest_expect("70000", "%ld", 70000); + utest_expect("0xb0001234", "%p", (void*)0xb0001234); + utest_expect("12ab", "%x", 0x12ab); + utest_expect("12AB", "%X", 0x12ab); + utest_expect("00123456", "%08x", 0x123456); + utest_expect("01234", "0%d", 1234); + utest_expect(" 1234", "%5d", 1234); + utest_expect("01234", "%05d", 1234); + utest_expect(" 1234", "%8d", 1234); + utest_expect("1234 ", "%-8d", 1234); + utest_expect("abcdef ", "%-11s", "abcdef"); + utest_expect("something:1234", "%s:%d", "something", 1234); + return gFails != 0; +} + +#endif /* UNIT_TESTS */ |