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Diffstat (limited to 'tools/perf/util/demangle-rust-v0.c')
-rw-r--r-- | tools/perf/util/demangle-rust-v0.c | 2042 |
1 files changed, 2042 insertions, 0 deletions
diff --git a/tools/perf/util/demangle-rust-v0.c b/tools/perf/util/demangle-rust-v0.c new file mode 100644 index 000000000000..19924d85407d --- /dev/null +++ b/tools/perf/util/demangle-rust-v0.c @@ -0,0 +1,2042 @@ +// SPDX-License-Identifier: Apache-2.0 OR MIT + +// The contents of this file come from the Rust rustc-demangle library, hosted +// in the <https://github.com/rust-lang/rustc-demangle> repository, licensed +// under "Apache-2.0 OR MIT". For copyright details, see +// <https://github.com/rust-lang/rustc-demangle/blob/main/README.md>. +// Please note that the file should be kept as close as possible to upstream. + +// Code for demangling Rust symbols. This code is mostly +// a line-by-line translation of the Rust code in `rustc-demangle`. + +// you can find the latest version of this code in https://github.com/rust-lang/rustc-demangle + +#include <stdint.h> +#include <stddef.h> +#include <string.h> +#include <stdbool.h> +#include <sys/param.h> +#include <stdio.h> + +#include "demangle-rust-v0.h" + +#if defined(__GNUC__) || defined(__clang__) +#define NODISCARD __attribute__((warn_unused_result)) +#else +#define NODISCARD +#endif + +#define MAX_DEPTH 500 + +typedef enum { + DemangleOk, + DemangleInvalid, + DemangleRecursed, + DemangleBug, +} demangle_status; + +struct demangle_v0 { + const char *mangled; + size_t mangled_len; +}; + +struct demangle_legacy { + const char *mangled; + size_t mangled_len; + size_t elements; +}; + +// private version of memrchr to avoid _GNU_SOURCE +static void *demangle_memrchr(const void *s, int c, size_t n) { + const uint8_t *s_ = s; + for (; n != 0; n--) { + if (s_[n-1] == c) { + return (void*)&s_[n-1]; + } + } + return NULL; +} + + +static bool unicode_iscontrol(uint32_t ch) { + // this is *technically* a unicode table, but + // some unicode properties are simpler than you might think + return ch < 0x20 || (ch >= 0x7f && ch < 0xa0); +} + +// "good enough" tables, the only consequence is that when printing +// *constant strings*, some characters are printed as `\u{abcd}` rather than themselves. +// +// I'm leaving these here to allow easily replacing them with actual +// tables if desired. +static bool unicode_isprint(uint32_t ch) { + if (ch < 0x20) { + return false; + } + if (ch < 0x7f) { + return true; + } + return false; +} + +static bool unicode_isgraphemextend(uint32_t ch) { + (void)ch; + return false; +} + +static bool str_isascii(const char *s, size_t s_len) { + for (size_t i = 0; i < s_len; i++) { + if (s[i] & 0x80) { + return false; + } + } + + return true; +} + +typedef enum { + PunycodeOk, + PunycodeError +} punycode_status; + +struct parser { + // the parser assumes that `sym` has a safe "terminating byte". It might be NUL, + // but it might also be something else if a symbol is "truncated". + const char *sym; + size_t sym_len; + size_t next; + uint32_t depth; +}; + +struct printer { + demangle_status status; // if status == 0 parser is valid + struct parser parser; + char *out; // NULL for no output [in which case out_len is not decremented] + size_t out_len; + uint32_t bound_lifetime_depth; + bool alternate; +}; + +static NODISCARD overflow_status printer_print_path(struct printer *printer, bool in_value); +static NODISCARD overflow_status printer_print_type(struct printer *printer); +static NODISCARD overflow_status printer_print_const(struct printer *printer, bool in_value); + +static NODISCARD demangle_status try_parse_path(struct parser *parser) { + struct printer printer = { + DemangleOk, + *parser, + NULL, + SIZE_MAX, + 0, + false + }; + overflow_status ignore = printer_print_path(&printer, false); // can't fail since no output + (void)ignore; + *parser = printer.parser; + return printer.status; +} + +NODISCARD static demangle_status rust_demangle_v0_demangle(const char *s, size_t s_len, struct demangle_v0 *res, const char **rest) { + if (s_len > strlen(s)) { + // s_len only exists to shorten the string, this is not a buffer API + return DemangleInvalid; + } + + const char *inner; + size_t inner_len; + if (s_len >= 2 && !strncmp(s, "_R", strlen("_R"))) { + inner = s+2; + inner_len = s_len - 2; + } else if (s_len >= 1 && !strncmp(s, "R", strlen("R"))) { + // On Windows, dbghelp strips leading underscores, so we accept "R..." + // form too. + inner = s+1; + inner_len = s_len - 1; + } else if (s_len >= 3 && !strncmp(s, "__R", strlen("__R"))) { + // On OSX, symbols are prefixed with an extra _ + inner = s+3; + inner_len = s_len - 3; + } else { + return DemangleInvalid; + } + + // Paths always start with uppercase characters. + if (*inner < 'A' || *inner > 'Z') { + return DemangleInvalid; + } + + if (!str_isascii(inner, inner_len)) { + return DemangleInvalid; + } + + struct parser parser = { inner, inner_len, 0, 0 }; + + demangle_status status = try_parse_path(&parser); + if (status != DemangleOk) return status; + char next = parser.sym[parser.next]; + + // Instantiating crate (paths always start with uppercase characters). + if (parser.next < parser.sym_len && next >= 'A' && next <= 'Z') { + status = try_parse_path(&parser); + if (status != DemangleOk) return status; + } + + res->mangled = inner; + res->mangled_len = inner_len; + if (rest) { + *rest = parser.sym + parser.next; + } + + return DemangleOk; +} + +// This might require `len` to be up to 3 characters bigger than the real output len in case of utf-8 +NODISCARD static overflow_status rust_demangle_v0_display_demangle(struct demangle_v0 res, char *out, size_t len, bool alternate) { + struct printer printer = { + DemangleOk, + { + res.mangled, + res.mangled_len, + 0, + 0 + }, + out, + len, + 0, + alternate + }; + if (printer_print_path(&printer, true) == OverflowOverflow) { + return OverflowOverflow; + } + if (printer.out_len < OVERFLOW_MARGIN) { + return OverflowOverflow; + } + *printer.out = '\0'; + return OverflowOk; +} + +static size_t code_to_utf8(unsigned char *buffer, uint32_t code) +{ + if (code <= 0x7F) { + buffer[0] = code; + return 1; + } + if (code <= 0x7FF) { + buffer[0] = 0xC0 | (code >> 6); /* 110xxxxx */ + buffer[1] = 0x80 | (code & 0x3F); /* 10xxxxxx */ + return 2; + } + if (code <= 0xFFFF) { + buffer[0] = 0xE0 | (code >> 12); /* 1110xxxx */ + buffer[1] = 0x80 | ((code >> 6) & 0x3F); /* 10xxxxxx */ + buffer[2] = 0x80 | (code & 0x3F); /* 10xxxxxx */ + return 3; + } + if (code <= 0x10FFFF) { + buffer[0] = 0xF0 | (code >> 18); /* 11110xxx */ + buffer[1] = 0x80 | ((code >> 12) & 0x3F); /* 10xxxxxx */ + buffer[2] = 0x80 | ((code >> 6) & 0x3F); /* 10xxxxxx */ + buffer[3] = 0x80 | (code & 0x3F); /* 10xxxxxx */ + return 4; + } + return 0; +} + + +// return length of char at byte, or SIZE_MAX if invalid. buf should have 4 valid characters +static NODISCARD size_t utf8_next_char(uint8_t *s, uint32_t *ch) { + uint8_t byte = *s; + // UTF8-1 = %x00-7F + // UTF8-2 = %xC2-DF UTF8-tail + // UTF8-3 = %xE0 %xA0-BF UTF8-tail / %xE1-EC 2( UTF8-tail ) / + // %xED %x80-9F UTF8-tail / %xEE-EF 2( UTF8-tail ) + // UTF8-4 = %xF0 %x90-BF 2( UTF8-tail ) / %xF1-F3 3( UTF8-tail ) / + // %xF4 %x80-8F 2( UTF8-tail ) + if (byte < 0x80) { + *ch = byte; + return 1; + } else if (byte < 0xc2) { + return SIZE_MAX; + } else if (byte < 0xe0) { + if (s[1] >= 0x80 && s[1] < 0xc0) { + *ch = ((byte&0x1f)<<6) + (s[1] & 0x3f); + return 2; + } + return SIZE_MAX; + } if (byte < 0xf0) { + if (!(s[1] >= 0x80 && s[1] < 0xc0) || !(s[2] >= 0x80 && s[2] < 0xc0)) { + return SIZE_MAX; // basic validation + } + if (byte == 0xe0 && s[1] < 0xa0) { + return SIZE_MAX; // overshort + } + if (byte == 0xed && s[1] >= 0xa0) { + return SIZE_MAX; // surrogate + } + *ch = ((byte&0x0f)<<12) + ((s[1] & 0x3f)<<6) + (s[2] & 0x3f); + return 3; + } else if (byte < 0xf5) { + if (!(s[1] >= 0x80 && s[1] < 0xc0) || !(s[2] >= 0x80 && s[2] < 0xc0) || !(s[3] >= 0x80 && s[3] < 0xc0)) { + return SIZE_MAX; // basic validation + } + if (byte == 0xf0 && s[1] < 0x90) { + return SIZE_MAX; // overshort + } + if (byte == 0xf4 && s[1] >= 0x90) { + return SIZE_MAX; // over max + } + *ch = ((byte&0x07)<<18) + ((s[1] & 0x3f)<<12) + ((s[2] & 0x3f)<<6) + (s[3]&0x3f); + return 4; + } else { + return SIZE_MAX; + } +} + +static NODISCARD bool validate_char(uint32_t n) { + return ((n ^ 0xd800) - 0x800) < 0x110000 - 0x800; +} + +#define SMALL_PUNYCODE_LEN 128 + +static NODISCARD punycode_status punycode_decode(const char *start, size_t ascii_len, const char *punycode_start, size_t punycode_len, uint32_t (*out_)[SMALL_PUNYCODE_LEN], size_t *out_len) { + uint32_t *out = *out_; + + if (punycode_len == 0) { + return PunycodeError; + } + + if (ascii_len > SMALL_PUNYCODE_LEN) { + return PunycodeError; + } + for (size_t i = 0; i < ascii_len; i++) { + out[i] = start[i]; + } + size_t len = ascii_len; + + size_t base = 36, t_min = 1, t_max = 26, skew = 38, damp = 700, bias = 72, i = 0, n = 0x80; + for (;;) { + size_t delta = 0, w = 1, k = 0; + for (;;) { + k += base; + size_t biased = k < bias ? 0 : k - bias; + size_t t = MIN(MAX(biased, t_min), t_max); + size_t d; + if (punycode_len == 0) { + return PunycodeError; + } + char nx = *punycode_start++; + punycode_len--; + if ('a' <= nx && nx <= 'z') { + d = nx - 'a'; + } else if ('0' <= nx && nx <= '9') { + d = 26 + (nx - '0'); + } else { + return PunycodeError; + } + if (w == 0 || d > SIZE_MAX / w || d*w > SIZE_MAX - delta) { + return PunycodeError; + } + delta += d * w; + if (d < t) { + break; + } + if (base < t || w == 0 || (base - t) > SIZE_MAX / w) { + return PunycodeError; + } + w *= (base - t); + } + + len += 1; + if (i > SIZE_MAX - delta) { + return PunycodeError; + } + i += delta; + if (n > SIZE_MAX - i / len) { + return PunycodeError; + } + n += i / len; + i %= len; + + // char validation + if (n > UINT32_MAX || !validate_char((uint32_t)n)) { + return PunycodeError; + } + + // insert new character + if (len > SMALL_PUNYCODE_LEN) { + return PunycodeError; + } + memmove(out + i + 1, out + i, (len - i - 1) * sizeof(uint32_t)); + out[i] = (uint32_t)n; + + // start i index at incremented position + i++; + + // If there are no more deltas, decoding is complete. + if (punycode_len == 0) { + *out_len = len; + return PunycodeOk; + } + + // Perform bias adaptation. + delta /= damp; + damp = 2; + + delta += delta / len; + k = 0; + while (delta > ((base - t_min) * t_max) / 2) { + delta /= base - t_min; + k += base; + } + bias = k + ((base - t_min + 1) * delta) / (delta + skew); + } +} + +struct ident { + const char *ascii_start; + size_t ascii_len; + const char *punycode_start; + size_t punycode_len; +}; + +static NODISCARD overflow_status display_ident(const char *ascii_start, size_t ascii_len, const char *punycode_start, size_t punycode_len, uint8_t *out, size_t *out_len) { + uint32_t outbuf[SMALL_PUNYCODE_LEN]; + + size_t wide_len; + size_t out_buflen = *out_len; + + if (punycode_len == 0) { + if (ascii_len > out_buflen) { + return OverflowOverflow; + } + memcpy(out, ascii_start, ascii_len); + *out_len = ascii_len; + } else if (punycode_decode(ascii_start, ascii_len, punycode_start, punycode_len, &outbuf, &wide_len) == PunycodeOk) { + size_t narrow_len = 0; + for (size_t i = 0; i < wide_len; i++) { + if (out_buflen - narrow_len < 4) { + return OverflowOverflow; + } + unsigned char *pos = &out[narrow_len]; + narrow_len += code_to_utf8(pos, outbuf[i]); + } + *out_len = narrow_len; + } else { + size_t narrow_len = 0; + if (out_buflen < strlen("punycode{")) { + return OverflowOverflow; + } + memcpy(out, "punycode{", strlen("punycode{")); + narrow_len = strlen("punycode{"); + if (ascii_len > 0) { + if (out_buflen - narrow_len < ascii_len || out_buflen - narrow_len - ascii_len < 1) { + return OverflowOverflow; + } + memcpy(out + narrow_len, ascii_start, ascii_len); + narrow_len += ascii_len; + out[narrow_len] = '-'; + narrow_len++; + } + if (out_buflen - narrow_len < punycode_len || out_buflen - narrow_len - punycode_len < 1) { + return OverflowOverflow; + } + memcpy(out + narrow_len, punycode_start, punycode_len); + narrow_len += punycode_len; + out[narrow_len] = '}'; + narrow_len++; + *out_len = narrow_len; + } + + return OverflowOk; +} + +static NODISCARD bool try_parse_uint(const char *buf, size_t len, uint64_t *result) { + size_t cur = 0; + for(;cur < len && buf[cur] == '0';cur++); + uint64_t result_val = 0; + if (len - cur > 16) return false; + for(;cur < len;cur++) { + char c = buf[cur]; + result_val <<= 4; + if ('0' <= c && c <= '9') { + result_val += c - '0'; + } else if ('a' <= c && c <= 'f') { + result_val += 10 + (c - 'a'); + } else { + return false; + } + } + *result = result_val; + return true; +} + +static NODISCARD bool dinibble2int(const char *buf, uint8_t *result) { + uint8_t result_val = 0; + for (int i = 0; i < 2; i++) { + char c = buf[i]; + result_val <<= 4; + if ('0' <= c && c <= '9') { + result_val += c - '0'; + } else if ('a' <= c && c <= 'f') { + result_val += 10 + (c - 'a'); + } else { + return false; + } + } + *result = result_val; + return true; +} + + +typedef enum { + NtsOk = 0, + NtsOverflow = 1, + NtsInvalid = 2 +} nibbles_to_string_status; + +// '\u{10ffff}', +margin +#define ESCAPED_SIZE 12 + +static NODISCARD size_t char_to_string(uint32_t ch, uint8_t quote, bool first, char (*buf)[ESCAPED_SIZE]) { + // encode the character + char *escaped_buf = *buf; + escaped_buf[0] = '\\'; + size_t escaped_len = 2; + switch (ch) { + case '\0': + escaped_buf[1] = '0'; + break; + case '\t': + escaped_buf[1] = 't'; + break; + case '\r': + escaped_buf[1] = 'r'; + break; + case '\n': + escaped_buf[1] = 'n'; + break; + case '\\': + escaped_buf[1] = '\\'; + break; + default: + if (ch == quote) { + escaped_buf[1] = ch; + } else if (!unicode_isprint(ch) || (first && unicode_isgraphemextend(ch))) { + int hexlen = snprintf(escaped_buf, ESCAPED_SIZE, "\\u{%x}", (unsigned int)ch); + if (hexlen < 0) { + return 0; // (snprintf shouldn't fail!) + } + escaped_len = hexlen; + } else { + // printable character + escaped_buf[0] = ch; + escaped_len = 1; + } + break; + } + + return escaped_len; +} + +// convert nibbles to a single/double-quoted string +static NODISCARD nibbles_to_string_status nibbles_to_string(const char *buf, size_t len, uint8_t *out, size_t *out_len) { + uint8_t quote = '"'; + bool first = true; + + if ((len % 2) != 0) { + return NtsInvalid; // odd number of nibbles + } + + size_t cur_out_len = 0; + + // write starting quote + if (out != NULL) { + cur_out_len = *out_len; + if (cur_out_len == 0) { + return NtsOverflow; + } + *out++ = quote; + cur_out_len--; + } + + uint8_t conv_buf[4] = {0}; + size_t conv_buf_len = 0; + while (len > 1 || conv_buf_len > 0) { + while (len > 1 && conv_buf_len < sizeof(conv_buf)) { + if (!dinibble2int(buf, &conv_buf[conv_buf_len])) { + return NtsInvalid; + } + conv_buf_len++; + buf += 2; + len -= 2; + } + + // conv_buf is full here if possible, process 1 UTF-8 character + uint32_t ch = 0; + size_t consumed = utf8_next_char(conv_buf, &ch); + if (consumed > conv_buf_len) { + // either SIZE_MAX (invalid UTF-8) or finished input buffer and + // there are still bytes remaining, in both cases invalid + return NtsInvalid; + } + + // "consume" the character + memmove(conv_buf, conv_buf+consumed, conv_buf_len-consumed); + conv_buf_len -= consumed; + + char escaped_buf[ESCAPED_SIZE]; + size_t escaped_len = char_to_string(ch, '"', first, &escaped_buf); + if (out != NULL) { + if (cur_out_len < escaped_len) { + return NtsOverflow; + } + memcpy(out, escaped_buf, escaped_len); + out += escaped_len; + cur_out_len -= escaped_len; + } + first = false; + } + + // write ending quote + if (out != NULL) { + if (cur_out_len == 0) { + return NtsOverflow; + } + *out++ = quote; + cur_out_len--; + *out_len -= cur_out_len; // subtract remaining space to get used space + } + + return NtsOk; +} + +static const char* basic_type(uint8_t tag) { + switch(tag) { + case 'b': + return "bool"; + case 'c': + return "char"; + case 'e': + return "str"; + case 'u': + return "()"; + case 'a': + return "i8"; + case 's': + return "i16"; + case 'l': + return "i32"; + case 'x': + return "i64"; + case 'n': + return "i128"; + case 'i': + return "isize"; + case 'h': + return "u8"; + case 't': + return "u16"; + case 'm': + return "u32"; + case 'y': + return "u64"; + case 'o': + return "u128"; + case 'j': + return "usize"; + case 'f': + return "f32"; + case 'd': + return "f64"; + case 'z': + return "!"; + case 'p': + return "_"; + case 'v': + return "..."; + default: + return NULL; + } +} + +static NODISCARD demangle_status parser_push_depth(struct parser *parser) { + parser->depth++; + if (parser->depth > MAX_DEPTH) { + return DemangleRecursed; + } else { + return DemangleOk; + } +} + +static demangle_status parser_pop_depth(struct parser *parser) { + parser->depth--; + return DemangleOk; +} + +static uint8_t parser_peek(struct parser const *parser) { + if (parser->next == parser->sym_len) { + return 0; // add a "pseudo nul terminator" to avoid peeking past the end of a symbol + } else { + return parser->sym[parser->next]; + } +} + +static bool parser_eat(struct parser *parser, uint8_t ch) { + if (parser_peek(parser) == ch) { + if (ch != 0) { // safety: make sure we don't skip past the NUL terminator + parser->next++; + } + return true; + } else { + return false; + } +} + +static uint8_t parser_next(struct parser *parser) { + // don't advance after end of input, and return an imaginary NUL terminator + if (parser->next == parser->sym_len) { + return 0; + } else { + return parser->sym[parser->next++]; + } +} + +static NODISCARD demangle_status parser_ch(struct parser *parser, uint8_t *next) { + // don't advance after end of input + if (parser->next == parser->sym_len) { + return DemangleInvalid; + } else { + *next = parser->sym[parser->next++]; + return DemangleOk; + } +} + +struct buf { + const char *start; + size_t len; +}; + +static NODISCARD demangle_status parser_hex_nibbles(struct parser *parser, struct buf *buf) { + size_t start = parser->next; + for (;;) { + uint8_t ch = parser_next(parser); + if (ch == '_') { + break; + } + if (!(('0' <= ch && ch <= '9') || ('a' <= ch && ch <= 'f'))) { + return DemangleInvalid; + } + } + buf->start = parser->sym + start; + buf->len = parser->next - start - 1; // skip final _ + return DemangleOk; +} + +static NODISCARD demangle_status parser_digit_10(struct parser *parser, uint8_t *out) { + uint8_t ch = parser_peek(parser); + if ('0' <= ch && ch <= '9') { + *out = ch - '0'; + parser->next++; + return DemangleOk; + } else { + return DemangleInvalid; + } +} + +static NODISCARD demangle_status parser_digit_62(struct parser *parser, uint64_t *out) { + uint8_t ch = parser_peek(parser); + if ('0' <= ch && ch <= '9') { + *out = ch - '0'; + parser->next++; + return DemangleOk; + } else if ('a' <= ch && ch <= 'z') { + *out = 10 + (ch - 'a'); + parser->next++; + return DemangleOk; + } else if ('A' <= ch && ch <= 'Z') { + *out = 10 + 26 + (ch - 'A'); + parser->next++; + return DemangleOk; + } else { + return DemangleInvalid; + } +} + +static NODISCARD demangle_status parser_integer_62(struct parser *parser, uint64_t *out) { + if (parser_eat(parser, '_')) { + *out = 0; + return DemangleOk; + } + + uint64_t x = 0; + demangle_status status; + while (!parser_eat(parser, '_')) { + uint64_t d; + if ((status = parser_digit_62(parser, &d)) != DemangleOk) { + return status; + } + if (x > UINT64_MAX / 62) { + return DemangleInvalid; + } + x *= 62; + if (x > UINT64_MAX - d) { + return DemangleInvalid; + } + x += d; + } + if (x == UINT64_MAX) { + return DemangleInvalid; + } + *out = x + 1; + return DemangleOk; +} + +static NODISCARD demangle_status parser_opt_integer_62(struct parser *parser, uint8_t tag, uint64_t *out) { + if (!parser_eat(parser, tag)) { + *out = 0; + return DemangleOk; + } + + demangle_status status; + if ((status = parser_integer_62(parser, out)) != DemangleOk) { + return status; + } + if (*out == UINT64_MAX) { + return DemangleInvalid; + } + *out = *out + 1; + return DemangleOk; +} + +static NODISCARD demangle_status parser_disambiguator(struct parser *parser, uint64_t *out) { + return parser_opt_integer_62(parser, 's', out); +} + +typedef uint8_t parser_namespace_type; + +static NODISCARD demangle_status parser_namespace(struct parser *parser, parser_namespace_type *out) { + uint8_t next = parser_next(parser); + if ('A' <= next && next <= 'Z') { + *out = next; + return DemangleOk; + } else if ('a' <= next && next <= 'z') { + *out = 0; + return DemangleOk; + } else { + return DemangleInvalid; + } +} + +static NODISCARD demangle_status parser_backref(struct parser *parser, struct parser *out) { + size_t start = parser->next; + if (start == 0) { + return DemangleBug; + } + size_t s_start = start - 1; + uint64_t i; + demangle_status status = parser_integer_62(parser, &i); + if (status != DemangleOk) { + return status; + } + if (i >= s_start) { + return DemangleInvalid; + } + struct parser res = { + .sym = parser->sym, + .sym_len = parser->sym_len, + .next = (size_t)i, + .depth = parser->depth + }; + status = parser_push_depth(&res); + if (status != DemangleOk) { + return status; + } + *out = res; + return DemangleOk; +} + +static NODISCARD demangle_status parser_ident(struct parser *parser, struct ident *out) { + bool is_punycode = parser_eat(parser, 'u'); + size_t len; + uint8_t d; + demangle_status status = parser_digit_10(parser, &d); + len = d; + if (status != DemangleOk) { + return status; + } + if (len) { + for (;;) { + status = parser_digit_10(parser, &d); + if (status != DemangleOk) { + break; + } + if (len > SIZE_MAX / 10) { + return DemangleInvalid; + } + len *= 10; + if (len > SIZE_MAX - d) { + return DemangleInvalid; + } + len += d; + } + } + + // Skip past the optional `_` separator. + parser_eat(parser, '_'); + + size_t start = parser->next; + if (parser->sym_len - parser->next < len) { + return DemangleInvalid; + } + parser->next += len; + + const char *ident = &parser->sym[start]; + + if (is_punycode) { + const char *underscore = demangle_memrchr(ident, '_', (size_t)len); + if (underscore == NULL) { + *out = (struct ident){ + .ascii_start="", + .ascii_len=0, + .punycode_start=ident, + .punycode_len=len + }; + } else { + size_t ascii_len = underscore - ident; + // ascii_len <= len - 1 since `_` is in the first len bytes + size_t punycode_len = len - 1 - ascii_len; + *out = (struct ident){ + .ascii_start=ident, + .ascii_len=ascii_len, + .punycode_start=underscore + 1, + .punycode_len=punycode_len + }; + } + if (out->punycode_len == 0) { + return DemangleInvalid; + } + return DemangleOk; + } else { + *out = (struct ident) { + .ascii_start=ident, + .ascii_len=(size_t)len, + .punycode_start="", + .punycode_len=0, + }; + return DemangleOk; + } +} + +#define INVALID_SYNTAX "{invalid syntax}" + +static const char *demangle_error_message(demangle_status status) { + switch (status) { + case DemangleInvalid: + return INVALID_SYNTAX; + case DemangleBug: + return "{bug}"; + case DemangleRecursed: + return "{recursion limit reached}"; + default: + return "{unknown error}"; + } +} + +#define PRINT(print_fn) \ + do { \ + if ((print_fn) == OverflowOverflow) { \ + return OverflowOverflow; \ + } \ + } while(0) + +#define PRINT_CH(printer, s) PRINT(printer_print_ch((printer), (s))) +#define PRINT_STR(printer, s) PRINT(printer_print_str((printer), (s))) +#define PRINT_U64(printer, s) PRINT(printer_print_u64((printer), (s))) +#define PRINT_IDENT(printer, s) PRINT(printer_print_ident((printer), (s))) + +#define INVALID(printer) \ + do { \ + PRINT_STR((printer), INVALID_SYNTAX); \ + (printer)->status = DemangleInvalid; \ + return OverflowOk; \ + } while(0) + +#define PARSE(printer, method, ...) \ + do { \ + if ((printer)->status != DemangleOk) { \ + PRINT_STR((printer), "?"); \ + return OverflowOk; \ + } else { \ + demangle_status _parse_status = method(&(printer)->parser, ## __VA_ARGS__); \ + if (_parse_status != DemangleOk) { \ + PRINT_STR((printer), demangle_error_message(_parse_status)); \ + (printer)->status = _parse_status; \ + return OverflowOk; \ + } \ + } \ + } while(0) + +#define PRINT_SEP_LIST(printer, body, sep) \ + do { \ + size_t _sep_list_i; \ + PRINT_SEP_LIST_COUNT(printer, _sep_list_i, body, sep); \ + } while(0) + +#define PRINT_SEP_LIST_COUNT(printer, count, body, sep) \ + do { \ + count = 0; \ + while ((printer)->status == DemangleOk && !printer_eat((printer), 'E')) { \ + if (count > 0) { PRINT_STR(printer, sep); } \ + body; \ + count++; \ + } \ + } while(0) + +static bool printer_eat(struct printer *printer, uint8_t b) { + if (printer->status != DemangleOk) { + return false; + } + + return parser_eat(&printer->parser, b); +} + +static void printer_pop_depth(struct printer *printer) { + if (printer->status == DemangleOk) { + parser_pop_depth(&printer->parser); + } +} + +static NODISCARD overflow_status printer_print_buf(struct printer *printer, const char *start, size_t len) { + if (printer->out == NULL) { + return OverflowOk; + } + if (printer->out_len < len) { + return OverflowOverflow; + } + + memcpy(printer->out, start, len); + printer->out += len; + printer->out_len -= len; + return OverflowOk; +} + +static NODISCARD overflow_status printer_print_str(struct printer *printer, const char *buf) { + return printer_print_buf(printer, buf, strlen(buf)); +} + +static NODISCARD overflow_status printer_print_ch(struct printer *printer, char ch) { + return printer_print_buf(printer, &ch, 1); +} + +static NODISCARD overflow_status printer_print_u64(struct printer *printer, uint64_t n) { + char buf[32] = {0}; + sprintf(buf, "%llu", (unsigned long long)n); // printing uint64 uses 21 < 32 chars + return printer_print_str(printer, buf); +} + +static NODISCARD overflow_status printer_print_ident(struct printer *printer, struct ident *ident) { + if (printer->out == NULL) { + return OverflowOk; + } + + size_t out_len = printer->out_len; + overflow_status status; + if ((status = display_ident(ident->ascii_start, ident->ascii_len, ident->punycode_start, ident->punycode_len, (uint8_t*)printer->out, &out_len)) != OverflowOk) { + return status; + } + printer->out += out_len; + printer->out_len -= out_len; + return OverflowOk; +} + +typedef overflow_status (*printer_fn)(struct printer *printer); +typedef overflow_status (*backref_fn)(struct printer *printer, bool *arg); + +static NODISCARD overflow_status printer_print_backref(struct printer *printer, backref_fn func, bool *arg) { + struct parser backref; + PARSE(printer, parser_backref, &backref); + + if (printer->out == NULL) { + return OverflowOk; + } + + struct parser orig_parser = printer->parser; + demangle_status orig_status = printer->status; // fixme not sure this is needed match for Ok on the Rust side + printer->parser = backref; + printer->status = DemangleOk; + overflow_status status = func(printer, arg); + printer->parser = orig_parser; + printer->status = orig_status; + + return status; +} + +static NODISCARD overflow_status printer_print_lifetime_from_index(struct printer *printer, uint64_t lt) { + // Bound lifetimes aren't tracked when skipping printing. + if (printer->out == NULL) { + return OverflowOk; + } + + PRINT_STR(printer, "'"); + if (lt == 0) { + PRINT_STR(printer, "_"); + return OverflowOk; + } + + if (printer->bound_lifetime_depth < lt) { + INVALID(printer); + } else { + uint64_t depth = printer->bound_lifetime_depth - lt; + if (depth < 26) { + PRINT_CH(printer, 'a' + depth); + } else { + PRINT_STR(printer, "_"); + PRINT_U64(printer, depth); + } + + return OverflowOk; + } +} + +static NODISCARD overflow_status printer_in_binder(struct printer *printer, printer_fn func) { + uint64_t bound_lifetimes; + PARSE(printer, parser_opt_integer_62, 'G', &bound_lifetimes); + + // Don't track bound lifetimes when skipping printing. + if (printer->out == NULL) { + return func(printer); + } + + if (bound_lifetimes > 0) { + PRINT_STR(printer, "for<"); + for (uint64_t i = 0; i < bound_lifetimes; i++) { + if (i > 0) { + PRINT_STR(printer, ", "); + } + printer->bound_lifetime_depth++; + PRINT(printer_print_lifetime_from_index(printer, 1)); + } + PRINT_STR(printer, "> "); + } + + overflow_status r = func(printer); + printer->bound_lifetime_depth -= bound_lifetimes; + + return r; +} + +static NODISCARD overflow_status printer_print_generic_arg(struct printer *printer) { + if (printer_eat(printer, 'L')) { + uint64_t lt; + PARSE(printer, parser_integer_62, <); + return printer_print_lifetime_from_index(printer, lt); + } else if (printer_eat(printer, 'K')) { + return printer_print_const(printer, false); + } else { + return printer_print_type(printer); + } +} + +static NODISCARD overflow_status printer_print_generic_args(struct printer *printer) { + PRINT_STR(printer, "<"); + PRINT_SEP_LIST(printer, PRINT(printer_print_generic_arg(printer)), ", "); + PRINT_STR(printer, ">"); + return OverflowOk; +} + +static NODISCARD overflow_status printer_print_path_out_of_value(struct printer *printer, bool *_arg) { + (void)_arg; + return printer_print_path(printer, false); +} + +static NODISCARD overflow_status printer_print_path_in_value(struct printer *printer, bool *_arg) { + (void)_arg; + return printer_print_path(printer, true); +} + +static NODISCARD overflow_status printer_print_path(struct printer *printer, bool in_value) { + PARSE(printer, parser_push_depth); + uint8_t tag; + PARSE(printer, parser_ch, &tag); + + overflow_status st; + uint64_t dis; + struct ident name; + parser_namespace_type ns; + char *orig_out; + + switch(tag) { + case 'C': + PARSE(printer, parser_disambiguator, &dis); + PARSE(printer, parser_ident, &name); + + PRINT_IDENT(printer, &name); + + if (printer->out != NULL && !printer->alternate && dis != 0) { + PRINT_STR(printer, "["); + char buf[24] = {0}; + sprintf(buf, "%llx", (unsigned long long)dis); + PRINT_STR(printer, buf); + PRINT_STR(printer, "]"); + } + break; + case 'N': + PARSE(printer, parser_namespace, &ns); + if ((st = printer_print_path(printer, in_value)) != OverflowOk) { + return st; + } + + // HACK(eddyb) if the parser is already marked as having errored, + // `parse!` below will print a `?` without its preceding `::` + // (because printing the `::` is skipped in certain conditions, + // i.e. a lowercase namespace with an empty identifier), + // so in order to get `::?`, the `::` has to be printed here. + if (printer->status != DemangleOk) { + PRINT_STR(printer, "::"); + } + + PARSE(printer, parser_disambiguator, &dis); + PARSE(printer, parser_ident, &name); + // Special namespace, like closures and shims + if (ns) { + PRINT_STR(printer, "::{"); + if (ns == 'C') { + PRINT_STR(printer, "closure"); + } else if (ns == 'S') { + PRINT_STR(printer, "shim"); + } else { + PRINT_CH(printer, ns); + } + if (name.ascii_len != 0 || name.punycode_len != 0) { + PRINT_STR(printer, ":"); + PRINT_IDENT(printer, &name); + } + PRINT_STR(printer, "#"); + PRINT_U64(printer, dis); + PRINT_STR(printer, "}"); + } else { + // Implementation-specific/unspecified namespaces + if (name.ascii_len != 0 || name.punycode_len != 0) { + PRINT_STR(printer, "::"); + PRINT_IDENT(printer, &name); + } + } + break; + case 'M': + case 'X': + // for impls, ignore the impls own path + PARSE(printer, parser_disambiguator, &dis); + orig_out = printer->out; + printer->out = NULL; + PRINT(printer_print_path(printer, false)); + printer->out = orig_out; + + // fallthru + case 'Y': + PRINT_STR(printer, "<"); + PRINT(printer_print_type(printer)); + if (tag != 'M') { + PRINT_STR(printer, " as "); + PRINT(printer_print_path(printer, false)); + } + PRINT_STR(printer, ">"); + break; + case 'I': + PRINT(printer_print_path(printer, in_value)); + if (in_value) { + PRINT_STR(printer, "::"); + } + PRINT(printer_print_generic_args(printer)); + break; + case 'B': + PRINT(printer_print_backref(printer, in_value ? printer_print_path_in_value : printer_print_path_out_of_value, NULL)); + break; + default: + INVALID(printer); + break; + } + + printer_pop_depth(printer); + return OverflowOk; +} + +static NODISCARD overflow_status printer_print_const_uint(struct printer *printer, uint8_t tag) { + struct buf hex; + PARSE(printer, parser_hex_nibbles, &hex); + + uint64_t val; + if (try_parse_uint(hex.start, hex.len, &val)) { + PRINT_U64(printer, val); + } else { + PRINT_STR(printer, "0x"); + PRINT(printer_print_buf(printer, hex.start, hex.len)); + } + + if (printer->out != NULL && !printer->alternate) { + const char *ty = basic_type(tag); + if (/* safety */ ty != NULL) { + PRINT_STR(printer, ty); + } + } + + return OverflowOk; +} + +static NODISCARD overflow_status printer_print_const_str_literal(struct printer *printer) { + struct buf hex; + PARSE(printer, parser_hex_nibbles, &hex); + + size_t out_len = SIZE_MAX; + nibbles_to_string_status nts_status = nibbles_to_string(hex.start, hex.len, NULL, &out_len); + switch (nts_status) { + case NtsOk: + if (printer->out != NULL) { + out_len = printer->out_len; + nts_status = nibbles_to_string(hex.start, hex.len, (uint8_t*)printer->out, &out_len); + if (nts_status != NtsOk) { + return OverflowOverflow; + } + printer->out += out_len; + printer->out_len -= out_len; + } + return OverflowOk; + case NtsOverflow: + // technically if there is a string of size `SIZE_MAX/6` whose escaped version overflows + // SIZE_MAX but has an invalid char, this will be a "fake" overflow. In practice, + // that is not going to happen and a fuzzer will not generate strings of this length. + return OverflowOverflow; + case NtsInvalid: + default: + INVALID(printer); + } +} + +static NODISCARD overflow_status printer_print_const_struct(struct printer *printer) { + uint64_t dis; + struct ident name; + PARSE(printer, parser_disambiguator, &dis); + PARSE(printer, parser_ident, &name); + PRINT_IDENT(printer, &name); + PRINT_STR(printer, ": "); + return printer_print_const(printer, true); +} + +static NODISCARD overflow_status printer_print_const_out_of_value(struct printer *printer, bool *_arg) { + (void)_arg; + return printer_print_const(printer, false); +} + +static NODISCARD overflow_status printer_print_const_in_value(struct printer *printer, bool *_arg) { + (void)_arg; + return printer_print_const(printer, true); +} + +static NODISCARD overflow_status printer_print_const(struct printer *printer, bool in_value) { + uint8_t tag; + + PARSE(printer, parser_ch, &tag); + PARSE(printer, parser_push_depth); + + struct buf hex; + uint64_t val; + size_t count; + + bool opened_brace = false; +#define OPEN_BRACE_IF_OUTSIDE_EXPR \ + do { if (!in_value) { \ + opened_brace = true; \ + PRINT_STR(printer, "{"); \ + } } while(0) + + switch(tag) { + case 'p': + PRINT_STR(printer, "_"); + break; + // Primitive leaves with hex-encoded values (see `basic_type`). + case 'a': + case 's': + case 'l': + case 'x': + case 'n': + case 'i': + if (printer_eat(printer, 'n')) { + PRINT_STR(printer, "-"); + } + /* fallthrough */ + case 'h': + case 't': + case 'm': + case 'y': + case 'o': + case 'j': + PRINT(printer_print_const_uint(printer, tag)); + break; + case 'b': + PARSE(printer, parser_hex_nibbles, &hex); + if (try_parse_uint(hex.start, hex.len, &val)) { + if (val == 0) { + PRINT_STR(printer, "false"); + } else if (val == 1) { + PRINT_STR(printer, "true"); + } else { + INVALID(printer); + } + } else { + INVALID(printer); + } + break; + case 'c': + PARSE(printer, parser_hex_nibbles, &hex); + if (try_parse_uint(hex.start, hex.len, &val) + && val < UINT32_MAX + && validate_char((uint32_t)val)) + { + char escaped_buf[ESCAPED_SIZE]; + size_t escaped_size = char_to_string((uint32_t)val, '\'', true, &escaped_buf); + + PRINT_STR(printer, "'"); + PRINT(printer_print_buf(printer, escaped_buf, escaped_size)); + PRINT_STR(printer, "'"); + } else { + INVALID(printer); + } + break; + case 'e': + OPEN_BRACE_IF_OUTSIDE_EXPR; + PRINT_STR(printer, "*"); + PRINT(printer_print_const_str_literal(printer)); + break; + case 'R': + case 'Q': + if (tag == 'R' && printer_eat(printer, 'e')) { + PRINT(printer_print_const_str_literal(printer)); + } else { + OPEN_BRACE_IF_OUTSIDE_EXPR; + PRINT_STR(printer, "&"); + if (tag != 'R') { + PRINT_STR(printer, "mut "); + } + PRINT(printer_print_const(printer, true)); + } + break; + case 'A': + OPEN_BRACE_IF_OUTSIDE_EXPR; + PRINT_STR(printer, "["); + PRINT_SEP_LIST(printer, PRINT(printer_print_const(printer, true)), ", "); + PRINT_STR(printer, "]"); + break; + case 'T': + OPEN_BRACE_IF_OUTSIDE_EXPR; + PRINT_STR(printer, "("); + PRINT_SEP_LIST_COUNT(printer, count, PRINT(printer_print_const(printer, true)), ", "); + if (count == 1) { + PRINT_STR(printer, ","); + } + PRINT_STR(printer, ")"); + break; + case 'V': + OPEN_BRACE_IF_OUTSIDE_EXPR; + PRINT(printer_print_path(printer, true)); + PARSE(printer, parser_ch, &tag); + switch(tag) { + case 'U': + break; + case 'T': + PRINT_STR(printer, "("); + PRINT_SEP_LIST(printer, PRINT(printer_print_const(printer, true)), ", "); + PRINT_STR(printer, ")"); + break; + case 'S': + PRINT_STR(printer, " { "); + PRINT_SEP_LIST(printer, PRINT(printer_print_const_struct(printer)), ", "); + PRINT_STR(printer, " }"); + break; + default: + INVALID(printer); + } + break; + case 'B': + PRINT(printer_print_backref(printer, in_value ? printer_print_const_in_value : printer_print_const_out_of_value, NULL)); + break; + default: + INVALID(printer); + } +#undef OPEN_BRACE_IF_OUTSIDE_EXPR + + if (opened_brace) { + PRINT_STR(printer, "}"); + } + printer_pop_depth(printer); + + return OverflowOk; +} + +/// A trait in a trait object may have some "existential projections" +/// (i.e. associated type bindings) after it, which should be printed +/// in the `<...>` of the trait, e.g. `dyn Trait<T, U, Assoc=X>`. +/// To this end, this method will keep the `<...>` of an 'I' path +/// open, by omitting the `>`, and return `Ok(true)` in that case. +static NODISCARD overflow_status printer_print_maybe_open_generics(struct printer *printer, bool *open) { + if (printer_eat(printer, 'B')) { + // NOTE(eddyb) the closure may not run if printing is being skipped, + // but in that case the returned boolean doesn't matter. + *open = false; + return printer_print_backref(printer, printer_print_maybe_open_generics, open); + } else if(printer_eat(printer, 'I')) { + PRINT(printer_print_path(printer, false)); + PRINT_STR(printer, "<"); + PRINT_SEP_LIST(printer, PRINT(printer_print_generic_arg(printer)), ", "); + *open = true; + return OverflowOk; + } else { + PRINT(printer_print_path(printer, false)); + *open = false; + return OverflowOk; + } +} + +static NODISCARD overflow_status printer_print_dyn_trait(struct printer *printer) { + bool open; + PRINT(printer_print_maybe_open_generics(printer, &open)); + + while (printer_eat(printer, 'p')) { + if (!open) { + PRINT_STR(printer, "<"); + open = true; + } else { + PRINT_STR(printer, ", "); + } + + struct ident name; + PARSE(printer, parser_ident, &name); + + PRINT_IDENT(printer, &name); + PRINT_STR(printer, " = "); + PRINT(printer_print_type(printer)); + } + + if (open) { + PRINT_STR(printer, ">"); + } + + return OverflowOk; +} + +static NODISCARD overflow_status printer_print_object_bounds(struct printer *printer) { + PRINT_SEP_LIST(printer, PRINT(printer_print_dyn_trait(printer)), " + "); + return OverflowOk; +} + +static NODISCARD overflow_status printer_print_function_type(struct printer *printer) { + bool is_unsafe = printer_eat(printer, 'U'); + const char *abi; + size_t abi_len; + if (printer_eat(printer, 'K')) { + if (printer_eat(printer, 'C')) { + abi = "C"; + abi_len = 1; + } else { + struct ident abi_ident; + PARSE(printer, parser_ident, &abi_ident); + if (abi_ident.ascii_len == 0 || abi_ident.punycode_len != 0) { + INVALID(printer); + } + abi = abi_ident.ascii_start; + abi_len = abi_ident.ascii_len; + } + } else { + abi = NULL; + abi_len = 0; + } + + if (is_unsafe) { + PRINT_STR(printer, "unsafe "); + } + + if (abi != NULL) { + PRINT_STR(printer, "extern \""); + + // replace _ with - + while (abi_len > 0) { + const char *minus = memchr(abi, '_', abi_len); + if (minus == NULL) { + PRINT(printer_print_buf(printer, (const char*)abi, abi_len)); + break; + } else { + size_t space_to_minus = minus - abi; + PRINT(printer_print_buf(printer, (const char*)abi, space_to_minus)); + PRINT_STR(printer, "-"); + abi = minus + 1; + abi_len -= (space_to_minus + 1); + } + } + + PRINT_STR(printer, "\" "); + } + + PRINT_STR(printer, "fn("); + PRINT_SEP_LIST(printer, PRINT(printer_print_type(printer)), ", "); + PRINT_STR(printer, ")"); + + if (printer_eat(printer, 'u')) { + // Skip printing the return type if it's 'u', i.e. `()`. + } else { + PRINT_STR(printer, " -> "); + PRINT(printer_print_type(printer)); + } + + return OverflowOk; +} + +static NODISCARD overflow_status printer_print_type_backref(struct printer *printer, bool *_arg) { + (void)_arg; + return printer_print_type(printer); +} + +static NODISCARD overflow_status printer_print_type(struct printer *printer) { + uint8_t tag; + PARSE(printer, parser_ch, &tag); + + const char *basic_ty = basic_type(tag); + if (basic_ty) { + return printer_print_str(printer, basic_ty); + } + + uint64_t count; + uint64_t lt; + + PARSE(printer, parser_push_depth); + switch (tag) { + case 'R': + case 'Q': + PRINT_STR(printer, "&"); + if (printer_eat(printer, 'L')) { + PARSE(printer, parser_integer_62, <); + if (lt != 0) { + PRINT(printer_print_lifetime_from_index(printer, lt)); + PRINT_STR(printer, " "); + } + } + if (tag != 'R') { + PRINT_STR(printer, "mut "); + } + PRINT(printer_print_type(printer)); + break; + case 'P': + case 'O': + PRINT_STR(printer, "*"); + if (tag != 'P') { + PRINT_STR(printer, "mut "); + } else { + PRINT_STR(printer, "const "); + } + PRINT(printer_print_type(printer)); + break; + case 'A': + case 'S': + PRINT_STR(printer, "["); + PRINT(printer_print_type(printer)); + if (tag == 'A') { + PRINT_STR(printer, "; "); + PRINT(printer_print_const(printer, true)); + } + PRINT_STR(printer, "]"); + break; + case 'T': + PRINT_STR(printer, "("); + PRINT_SEP_LIST_COUNT(printer, count, PRINT(printer_print_type(printer)), ", "); + if (count == 1) { + PRINT_STR(printer, ","); + } + PRINT_STR(printer, ")"); + break; + case 'F': + PRINT(printer_in_binder(printer, printer_print_function_type)); + break; + case 'D': + PRINT_STR(printer, "dyn "); + PRINT(printer_in_binder(printer, printer_print_object_bounds)); + + if (!printer_eat(printer, 'L')) { + INVALID(printer); + } + PARSE(printer, parser_integer_62, <); + + if (lt != 0) { + PRINT_STR(printer, " + "); + PRINT(printer_print_lifetime_from_index(printer, lt)); + } + break; + case 'B': + PRINT(printer_print_backref(printer, printer_print_type_backref, NULL)); + break; + default: + // Go back to the tag, so `print_path` also sees it. + if (printer->status == DemangleOk && /* safety */ printer->parser.next > 0) { + printer->parser.next--; + } + PRINT(printer_print_path(printer, false)); + } + + printer_pop_depth(printer); + return OverflowOk; +} + +NODISCARD static demangle_status rust_demangle_legacy_demangle(const char *s, size_t s_len, struct demangle_legacy *res, const char **rest) +{ + if (s_len > strlen(s)) { + // s_len only exists to shorten the string, this is not a buffer API + return DemangleInvalid; + } + + const char *inner; + size_t inner_len; + if (s_len >= 3 && !strncmp(s, "_ZN", 3)) { + inner = s + 3; + inner_len = s_len - 3; + } else if (s_len >= 2 && !strncmp(s, "ZN", 2)) { + // On Windows, dbghelp strips leading underscores, so we accept "ZN...E" + // form too. + inner = s + 2; + inner_len = s_len - 2; + } else if (s_len >= 4 && !strncmp(s, "__ZN", 4)) { + // On OSX, symbols are prefixed with an extra _ + inner = s + 4; + inner_len = s_len - 4; + } else { + return DemangleInvalid; + } + + if (!str_isascii(inner, inner_len)) { + return DemangleInvalid; + } + + size_t elements = 0; + const char *chars = inner; + size_t chars_len = inner_len; + if (chars_len == 0) { + return DemangleInvalid; + } + char c; + while ((c = *chars) != 'E') { + // Decode an identifier element's length + if (c < '0' || c > '9') { + return DemangleInvalid; + } + size_t len = 0; + while (c >= '0' && c <= '9') { + size_t d = c - '0'; + if (len > SIZE_MAX / 10) { + return DemangleInvalid; + } + len *= 10; + if (len > SIZE_MAX - d) { + return DemangleInvalid; + } + len += d; + + chars++; + chars_len--; + if (chars_len == 0) { + return DemangleInvalid; + } + c = *chars; + } + + // Advance by the length + if (chars_len <= len) { + return DemangleInvalid; + } + chars += len; + chars_len -= len; + elements++; + } + *res = (struct demangle_legacy) { inner, inner_len, elements }; + *rest = chars + 1; + return DemangleOk; +} + +static bool is_rust_hash(const char *s, size_t len) { + if (len == 0 || s[0] != 'h') { + return false; + } + + for (size_t i = 1; i < len; i++) { + if (!((s[i] >= '0' && s[i] <= '9') || (s[i] >= 'a' && s[i] <= 'f') || (s[i] >= 'A' && s[i] <= 'F'))) { + return false; + } + } + + return true; +} + +NODISCARD static overflow_status rust_demangle_legacy_display_demangle(struct demangle_legacy res, char *out, size_t len, bool alternate) +{ + struct printer printer = { + // not actually using the parser part of the printer, just keeping it to share the format functions + DemangleOk, + { NULL }, + out, + len, + 0, + alternate + }; + const char *inner = res.mangled; + for (size_t element = 0; element < res.elements; element++) { + size_t i = 0; + const char *rest; + for (rest = inner; rest < res.mangled + res.mangled_len && *rest >= '0' && *rest <= '9'; rest++) { + i *= 10; + i += *rest - '0'; + } + if ((size_t)(res.mangled + res.mangled_len - rest) < i) { + // safety: shouldn't reach this place if the input string is validated. bail out. + // safety: we knwo rest <= res.mangled + res.mangled_len from the for-loop above + break; + } + + size_t len = i; + inner = rest + len; + + // From here on, inner contains a pointer to the next element, rest[:len] to the current one + if (alternate && element + 1 == res.elements && is_rust_hash(rest, i)) { + break; + } + if (element != 0) { + PRINT_STR(&printer, "::"); + } + + if (len >= 2 && !strncmp(rest, "_$", 2)) { + rest++; + len--; + } + + while (len > 0) { + if (rest[0] == '.') { + if (len >= 2 && rest[1] == '.') { + PRINT_STR(&printer, "::"); + rest += 2; + len -= 2; + } else { + PRINT_STR(&printer, "."); + rest += 1; + len -= 1; + } + } else if (rest[0] == '$') { + const char *escape = memchr(rest + 1, '$', len - 1); + if (escape == NULL) { + break; + } + const char *escape_start = rest + 1; + size_t escape_len = escape - (rest + 1); + + size_t next_len = len - (escape + 1 - rest); + const char *next_rest = escape + 1; + + char ch; + if ((escape_len == 2 && escape_start[0] == 'S' && escape_start[1] == 'P')) { + ch = '@'; + } else if ((escape_len == 2 && escape_start[0] == 'B' && escape_start[1] == 'P')) { + ch = '*'; + } else if ((escape_len == 2 && escape_start[0] == 'R' && escape_start[1] == 'F')) { + ch = '&'; + } else if ((escape_len == 2 && escape_start[0] == 'L' && escape_start[1] == 'T')) { + ch = '<'; + } else if ((escape_len == 2 && escape_start[0] == 'G' && escape_start[1] == 'T')) { + ch = '>'; + } else if ((escape_len == 2 && escape_start[0] == 'L' && escape_start[1] == 'P')) { + ch = '('; + } else if ((escape_len == 2 && escape_start[0] == 'R' && escape_start[1] == 'P')) { + ch = ')'; + } else if ((escape_len == 1 && escape_start[0] == 'C')) { + ch = ','; + } else { + if (escape_len > 1 && escape_start[0] == 'u') { + escape_start++; + escape_len--; + uint64_t val; + if (try_parse_uint(escape_start, escape_len, &val) + && val < UINT32_MAX + && validate_char((uint32_t)val)) + { + if (!unicode_iscontrol(val)) { + uint8_t wchr[4]; + size_t wchr_len = code_to_utf8(wchr, (uint32_t)val); + PRINT(printer_print_buf(&printer, (const char*)wchr, wchr_len)); + len = next_len; + rest = next_rest; + continue; + } + } + } + break; // print the rest of this element raw + } + PRINT_CH(&printer, ch); + len = next_len; + rest = next_rest; + } else { + size_t j = 0; + for (;j < len && rest[j] != '$' && rest[j] != '.';j++); + if (j == len) { + break; + } + PRINT(printer_print_buf(&printer, rest, j)); + rest += j; + len -= j; + } + } + PRINT(printer_print_buf(&printer, rest, len)); + } + + if (printer.out_len < OVERFLOW_MARGIN) { + return OverflowOverflow; + } + *printer.out = '\0'; + return OverflowOk; +} + +static bool is_symbol_like(const char *s, size_t len) { + // rust-demangle definition of symbol like: control characters and space are not symbol-like, all else is + for (size_t i = 0; i < len; i++) { + char ch = s[i]; + if (!(ch >= 0x21 && ch <= 0x7e)) { + return false; + } + } + return true; +} + +void rust_demangle_demangle(const char *s, struct demangle *res) +{ + // During ThinLTO LLVM may import and rename internal symbols, so strip out + // those endings first as they're one of the last manglings applied to symbol + // names. + const char *llvm = ".llvm."; + const char *found_llvm = strstr(s, llvm); + size_t s_len = strlen(s); + if (found_llvm) { + const char *all_hex_ptr = found_llvm + strlen(".llvm."); + bool all_hex = true; + for (;*all_hex_ptr;all_hex_ptr++) { + if (!(('0' <= *all_hex_ptr && *all_hex_ptr <= '9') || + ('A' <= *all_hex_ptr && *all_hex_ptr <= 'F') || + *all_hex_ptr == '@')) { + all_hex = false; + break; + } + } + + if (all_hex) { + s_len = found_llvm - s; + } + } + + const char *suffix; + struct demangle_legacy legacy; + demangle_status st = rust_demangle_legacy_demangle(s, s_len, &legacy, &suffix); + if (st == DemangleOk) { + *res = (struct demangle) { + .style=DemangleStyleLegacy, + .mangled=legacy.mangled, + .mangled_len=legacy.mangled_len, + .elements=legacy.elements, + .original=s, + .original_len=s_len, + .suffix=suffix, + .suffix_len=s_len - (suffix - s), + }; + } else { + struct demangle_v0 v0; + st = rust_demangle_v0_demangle(s, s_len, &v0, &suffix); + if (st == DemangleOk) { + *res = (struct demangle) { + .style=DemangleStyleV0, + .mangled=v0.mangled, + .mangled_len=v0.mangled_len, + .elements=0, + .original=s, + .original_len=s_len, + .suffix=suffix, + .suffix_len=s_len - (suffix - s), + }; + } else { + *res = (struct demangle) { + .style=DemangleStyleUnknown, + .mangled=NULL, + .mangled_len=0, + .elements=0, + .original=s, + .original_len=s_len, + .suffix=s, + .suffix_len=0, + }; + } + } + + // Output like LLVM IR adds extra period-delimited words. See if + // we are in that case and save the trailing words if so. + if (res->suffix_len) { + if (res->suffix[0] == '.' && is_symbol_like(res->suffix, res->suffix_len)) { + // Keep the suffix + } else { + // Reset the suffix and invalidate the demangling + res->style = DemangleStyleUnknown; + res->suffix_len = 0; + } + } +} + +bool rust_demangle_is_known(struct demangle *res) { + return res->style != DemangleStyleUnknown; +} + +overflow_status rust_demangle_display_demangle(struct demangle const *res, char *out, size_t len, bool alternate) { + size_t original_len = res->original_len; + size_t out_len; + switch (res->style) { + case DemangleStyleUnknown: + if (len < original_len) { + return OverflowOverflow; + } else { + memcpy(out, res->original, original_len); + out += original_len; + len -= original_len; + break; + } + break; + case DemangleStyleLegacy: { + struct demangle_legacy legacy = { + res->mangled, + res->mangled_len, + res->elements + }; + if (rust_demangle_legacy_display_demangle(legacy, out, len, alternate) == OverflowOverflow) { + return OverflowOverflow; + } + out_len = strlen(out); + out += out_len; + len -= out_len; + break; + } + case DemangleStyleV0: { + struct demangle_v0 v0 = { + res->mangled, + res->mangled_len + }; + if (rust_demangle_v0_display_demangle(v0, out, len, alternate) == OverflowOverflow) { + return OverflowOverflow; + } + out_len = strlen(out); + out += out_len; + len -= out_len; + break; + } + } + size_t suffix_len = res->suffix_len; + if (len < suffix_len || len - suffix_len < OVERFLOW_MARGIN) { + return OverflowOverflow; + } + memcpy(out, res->suffix, suffix_len); + out[suffix_len] = 0; + return OverflowOk; +} |