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Diffstat (limited to 'src/string.c')
| -rw-r--r-- | src/string.c | 204 |
1 files changed, 204 insertions, 0 deletions
diff --git a/src/string.c b/src/string.c new file mode 100644 index 00000000..cde82134 --- /dev/null +++ b/src/string.c @@ -0,0 +1,204 @@ +/* + Copyright 2011-2016 David Robillard <http://drobilla.net> + + Permission to use, copy, modify, and/or distribute this software for any + purpose with or without fee is hereby granted, provided that the above + copyright notice and this permission notice appear in all copies. + + THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. +*/ + +#include "serd_internal.h" + +#include <math.h> + +void +serd_free(void* ptr) +{ + free(ptr); +} + +const uint8_t* +serd_strerror(SerdStatus status) +{ + switch (status) { + case SERD_SUCCESS: return (const uint8_t*)"Success"; + case SERD_FAILURE: return (const uint8_t*)"Non-fatal failure"; + case SERD_ERR_UNKNOWN: return (const uint8_t*)"Unknown error"; + case SERD_ERR_BAD_SYNTAX: return (const uint8_t*)"Invalid syntax"; + case SERD_ERR_BAD_ARG: return (const uint8_t*)"Invalid argument"; + case SERD_ERR_NOT_FOUND: return (const uint8_t*)"Not found"; + case SERD_ERR_ID_CLASH: return (const uint8_t*)"Blank node ID clash"; + case SERD_ERR_BAD_CURIE: return (const uint8_t*)"Invalid CURIE"; + case SERD_ERR_INTERNAL: return (const uint8_t*)"Internal error"; + } + return (const uint8_t*)"Unknown error"; // never reached +} + +static inline void +serd_update_flags(const uint8_t c, SerdNodeFlags* const flags) +{ + switch (c) { + case '\r': case '\n': + *flags |= SERD_HAS_NEWLINE; + break; + case '"': + *flags |= SERD_HAS_QUOTE; + } +} + +size_t +serd_substrlen(const uint8_t* const str, + const size_t len, + size_t* const n_bytes, + SerdNodeFlags* const flags) +{ + size_t n_chars = 0; + size_t i = 0; + SerdNodeFlags f = 0; + for (; i < len && str[i]; ++i) { + if ((str[i] & 0xC0) != 0x80) { // Start of new character + ++n_chars; + serd_update_flags(str[i], &f); + } + } + if (n_bytes) { + *n_bytes = i; + } + if (flags) { + *flags = f; + } + return n_chars; +} + +size_t +serd_strlen(const uint8_t* str, size_t* n_bytes, SerdNodeFlags* flags) +{ + size_t n_chars = 0; + size_t i = 0; + SerdNodeFlags f = 0; + for (; str[i]; ++i) { + if ((str[i] & 0xC0) != 0x80) { // Start of new character + ++n_chars; + serd_update_flags(str[i], &f); + } + } + if (n_bytes) { + *n_bytes = i; + } + if (flags) { + *flags = f; + } + return n_chars; +} + +static inline double +read_sign(const char** sptr) +{ + double sign = 1.0; + switch (**sptr) { + case '-': + sign = -1.0; + // fallthru + case '+': + ++(*sptr); + // fallthru + default: + return sign; + } +} + +double +serd_strtod(const char* str, char** endptr) +{ + double result = 0.0; + + // Point s at the first non-whitespace character + const char* s = str; + while (is_space(*s)) { ++s; } + + // Read leading sign if necessary + const double sign = read_sign(&s); + + // Parse integer part + for (; is_digit(*s); ++s) { + result = (result * 10.0) + (*s - '0'); + } + + // Parse fractional part + if (*s == '.') { + double denom = 10.0; + for (++s; is_digit(*s); ++s) { + result += (*s - '0') / denom; + denom *= 10.0; + } + } + + // Parse exponent + if (*s == 'e' || *s == 'E') { + ++s; + double expt = 0.0; + double expt_sign = read_sign(&s); + for (; is_digit(*s); ++s) { + expt = (expt * 10.0) + (*s - '0'); + } + result *= pow(10, expt * expt_sign); + } + + if (endptr) { + *endptr = (char*)s; + } + + return result * sign; +} + +/** + Base64 decoding table. + This is indexed by encoded characters and returns the numeric value used + for decoding, shifted up by 47 to be in the range of printable ASCII. + A '$' is a placeholder for characters not in the base64 alphabet. +*/ +static const char b64_unmap[] = + "$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$m$$$ncdefghijkl$$$$$$" + "$/0123456789:;<=>?@ABCDEFGH$$$$$$IJKLMNOPQRSTUVWXYZ[\\]^_`ab$$$$" + "$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$" + "$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$"; + +static inline uint8_t unmap(const uint8_t in) { return b64_unmap[in] - 47; } + +/** + Decode 4 base64 characters to 3 raw bytes. +*/ +static inline size_t +decode_chunk(const uint8_t in[4], uint8_t out[3]) +{ + out[0] = (uint8_t)(((unmap(in[0]) << 2)) | unmap(in[1]) >> 4); + out[1] = (uint8_t)(((unmap(in[1]) << 4) & 0xF0) | unmap(in[2]) >> 2); + out[2] = (uint8_t)(((unmap(in[2]) << 6) & 0xC0) | unmap(in[3])); + return 1 + (in[2] != '=') + ((in[2] != '=') && (in[3] != '=')); +} + +void* +serd_base64_decode(const uint8_t* str, size_t len, size_t* size) +{ + void* buf = malloc((len * 3) / 4 + 2); + *size = 0; + for (size_t i = 0, j = 0; i < len; j += 3) { + uint8_t in[] = "===="; + size_t n_in = 0; + for (; i < len && n_in < 4; ++n_in) { + for (; i < len && !is_base64(str[i]); ++i) {} // Skip junk + in[n_in] = str[i++]; + } + if (n_in > 1) { + *size += decode_chunk(in, (uint8_t*)buf + j); + } + } + return buf; +} |