diff options
Diffstat (limited to 'util/buffer.c')
| -rw-r--r-- | util/buffer.c | 1046 |
1 files changed, 1046 insertions, 0 deletions
diff --git a/util/buffer.c b/util/buffer.c new file mode 100644 index 000000000..328fdfe7f --- /dev/null +++ b/util/buffer.c @@ -0,0 +1,1046 @@ +/* + * Copyright (C) the libgit2 contributors. All rights reserved. + * + * This file is part of libgit2, distributed under the GNU GPL v2 with + * a Linking Exception. For full terms see the included COPYING file. + */ +#include "buffer.h" +#include "posix.h" +#include "git2/buffer.h" +#include "buf_text.h" +#include <ctype.h> + +/* Used as default value for git_buf->ptr so that people can always + * assume ptr is non-NULL and zero terminated even for new git_bufs. + */ +char git_buf__initbuf[1]; + +char git_buf__oom[1]; + +#define ENSURE_SIZE(b, d) \ + if ((b)->ptr == git_buf__oom || \ + ((d) > (b)->asize && git_buf_grow((b), (d)) < 0))\ + return -1; + + +int git_buf_init(git_buf *buf, size_t initial_size) +{ + buf->asize = 0; + buf->size = 0; + buf->ptr = git_buf__initbuf; + + ENSURE_SIZE(buf, initial_size); + + return 0; +} + +int git_buf_try_grow( + git_buf *buf, size_t target_size, bool mark_oom) +{ + char *new_ptr; + size_t new_size; + + if (buf->ptr == git_buf__oom) + return -1; + + if (buf->asize == 0 && buf->size != 0) { + git_error_set(GIT_ERROR_INVALID, "cannot grow a borrowed buffer"); + return GIT_EINVALID; + } + + if (!target_size) + target_size = buf->size; + + if (target_size <= buf->asize) + return 0; + + if (buf->asize == 0) { + new_size = target_size; + new_ptr = NULL; + } else { + new_size = buf->asize; + /* + * Grow the allocated buffer by 1.5 to allow + * re-use of memory holes resulting from the + * realloc. If this is still too small, then just + * use the target size. + */ + if ((new_size = (new_size << 1) - (new_size >> 1)) < target_size) + new_size = target_size; + new_ptr = buf->ptr; + } + + /* round allocation up to multiple of 8 */ + new_size = (new_size + 7) & ~7; + + if (new_size < buf->size) { + if (mark_oom) { + if (buf->ptr && buf->ptr != git_buf__initbuf) + git__free(buf->ptr); + buf->ptr = git_buf__oom; + } + + git_error_set_oom(); + return -1; + } + + new_ptr = git__realloc(new_ptr, new_size); + + if (!new_ptr) { + if (mark_oom) { + if (buf->ptr && (buf->ptr != git_buf__initbuf)) + git__free(buf->ptr); + buf->ptr = git_buf__oom; + } + return -1; + } + + buf->asize = new_size; + buf->ptr = new_ptr; + + /* truncate the existing buffer size if necessary */ + if (buf->size >= buf->asize) + buf->size = buf->asize - 1; + buf->ptr[buf->size] = '\0'; + + return 0; +} + +int git_buf_grow(git_buf *buffer, size_t target_size) +{ + return git_buf_try_grow(buffer, target_size, true); +} + +int git_buf_grow_by(git_buf *buffer, size_t additional_size) +{ + size_t newsize; + + if (GIT_ADD_SIZET_OVERFLOW(&newsize, buffer->size, additional_size)) { + buffer->ptr = git_buf__oom; + return -1; + } + + return git_buf_try_grow(buffer, newsize, true); +} + +void git_buf_dispose(git_buf *buf) +{ + if (!buf) return; + + if (buf->asize > 0 && buf->ptr != NULL && buf->ptr != git_buf__oom) + git__free(buf->ptr); + + git_buf_init(buf, 0); +} + +void git_buf_free(git_buf *buf) +{ + git_buf_dispose(buf); +} + +void git_buf_sanitize(git_buf *buf) +{ + if (buf->ptr == NULL) { + assert(buf->size == 0 && buf->asize == 0); + buf->ptr = git_buf__initbuf; + } else if (buf->asize > buf->size) + buf->ptr[buf->size] = '\0'; +} + +void git_buf_clear(git_buf *buf) +{ + buf->size = 0; + + if (!buf->ptr) { + buf->ptr = git_buf__initbuf; + buf->asize = 0; + } + + if (buf->asize > 0) + buf->ptr[0] = '\0'; +} + +int git_buf_set(git_buf *buf, const void *data, size_t len) +{ + size_t alloclen; + + if (len == 0 || data == NULL) { + git_buf_clear(buf); + } else { + if (data != buf->ptr) { + GIT_ERROR_CHECK_ALLOC_ADD(&alloclen, len, 1); + ENSURE_SIZE(buf, alloclen); + memmove(buf->ptr, data, len); + } + + buf->size = len; + if (buf->asize > buf->size) + buf->ptr[buf->size] = '\0'; + + } + return 0; +} + +int git_buf_is_binary(const git_buf *buf) +{ + return git_buf_text_is_binary(buf); +} + +int git_buf_contains_nul(const git_buf *buf) +{ + return git_buf_text_contains_nul(buf); +} + +int git_buf_sets(git_buf *buf, const char *string) +{ + return git_buf_set(buf, string, string ? strlen(string) : 0); +} + +int git_buf_putc(git_buf *buf, char c) +{ + size_t new_size; + GIT_ERROR_CHECK_ALLOC_ADD(&new_size, buf->size, 2); + ENSURE_SIZE(buf, new_size); + buf->ptr[buf->size++] = c; + buf->ptr[buf->size] = '\0'; + return 0; +} + +int git_buf_putcn(git_buf *buf, char c, size_t len) +{ + size_t new_size; + GIT_ERROR_CHECK_ALLOC_ADD(&new_size, buf->size, len); + GIT_ERROR_CHECK_ALLOC_ADD(&new_size, new_size, 1); + ENSURE_SIZE(buf, new_size); + memset(buf->ptr + buf->size, c, len); + buf->size += len; + buf->ptr[buf->size] = '\0'; + return 0; +} + +int git_buf_put(git_buf *buf, const char *data, size_t len) +{ + if (len) { + size_t new_size; + + assert(data); + + GIT_ERROR_CHECK_ALLOC_ADD(&new_size, buf->size, len); + GIT_ERROR_CHECK_ALLOC_ADD(&new_size, new_size, 1); + ENSURE_SIZE(buf, new_size); + memmove(buf->ptr + buf->size, data, len); + buf->size += len; + buf->ptr[buf->size] = '\0'; + } + return 0; +} + +int git_buf_puts(git_buf *buf, const char *string) +{ + assert(string); + return git_buf_put(buf, string, strlen(string)); +} + +static const char base64_encode[] = + "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; + +int git_buf_encode_base64(git_buf *buf, const char *data, size_t len) +{ + size_t extra = len % 3; + uint8_t *write, a, b, c; + const uint8_t *read = (const uint8_t *)data; + size_t blocks = (len / 3) + !!extra, alloclen; + + GIT_ERROR_CHECK_ALLOC_ADD(&blocks, blocks, 1); + GIT_ERROR_CHECK_ALLOC_MULTIPLY(&alloclen, blocks, 4); + GIT_ERROR_CHECK_ALLOC_ADD(&alloclen, alloclen, buf->size); + + ENSURE_SIZE(buf, alloclen); + write = (uint8_t *)&buf->ptr[buf->size]; + + /* convert each run of 3 bytes into 4 output bytes */ + for (len -= extra; len > 0; len -= 3) { + a = *read++; + b = *read++; + c = *read++; + + *write++ = base64_encode[a >> 2]; + *write++ = base64_encode[(a & 0x03) << 4 | b >> 4]; + *write++ = base64_encode[(b & 0x0f) << 2 | c >> 6]; + *write++ = base64_encode[c & 0x3f]; + } + + if (extra > 0) { + a = *read++; + b = (extra > 1) ? *read++ : 0; + + *write++ = base64_encode[a >> 2]; + *write++ = base64_encode[(a & 0x03) << 4 | b >> 4]; + *write++ = (extra > 1) ? base64_encode[(b & 0x0f) << 2] : '='; + *write++ = '='; + } + + buf->size = ((char *)write) - buf->ptr; + buf->ptr[buf->size] = '\0'; + + return 0; +} + +/* The inverse of base64_encode */ +static const int8_t base64_decode[] = { + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63, + 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, 0, -1, -1, + -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, + 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1, + -1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, + 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 +}; + +int git_buf_decode_base64(git_buf *buf, const char *base64, size_t len) +{ + size_t i; + int8_t a, b, c, d; + size_t orig_size = buf->size, new_size; + + if (len % 4) { + git_error_set(GIT_ERROR_INVALID, "invalid base64 input"); + return -1; + } + + assert(len % 4 == 0); + GIT_ERROR_CHECK_ALLOC_ADD(&new_size, (len / 4 * 3), buf->size); + GIT_ERROR_CHECK_ALLOC_ADD(&new_size, new_size, 1); + ENSURE_SIZE(buf, new_size); + + for (i = 0; i < len; i += 4) { + if ((a = base64_decode[(unsigned char)base64[i]]) < 0 || + (b = base64_decode[(unsigned char)base64[i+1]]) < 0 || + (c = base64_decode[(unsigned char)base64[i+2]]) < 0 || + (d = base64_decode[(unsigned char)base64[i+3]]) < 0) { + buf->size = orig_size; + buf->ptr[buf->size] = '\0'; + + git_error_set(GIT_ERROR_INVALID, "invalid base64 input"); + return -1; + } + + buf->ptr[buf->size++] = ((a << 2) | (b & 0x30) >> 4); + buf->ptr[buf->size++] = ((b & 0x0f) << 4) | ((c & 0x3c) >> 2); + buf->ptr[buf->size++] = (c & 0x03) << 6 | (d & 0x3f); + } + + buf->ptr[buf->size] = '\0'; + return 0; +} + +static const char base85_encode[] = + "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz!#$%&()*+-;<=>?@^_`{|}~"; + +int git_buf_encode_base85(git_buf *buf, const char *data, size_t len) +{ + size_t blocks = (len / 4) + !!(len % 4), alloclen; + + GIT_ERROR_CHECK_ALLOC_MULTIPLY(&alloclen, blocks, 5); + GIT_ERROR_CHECK_ALLOC_ADD(&alloclen, alloclen, buf->size); + GIT_ERROR_CHECK_ALLOC_ADD(&alloclen, alloclen, 1); + + ENSURE_SIZE(buf, alloclen); + + while (len) { + uint32_t acc = 0; + char b85[5]; + int i; + + for (i = 24; i >= 0; i -= 8) { + uint8_t ch = *data++; + acc |= ch << i; + + if (--len == 0) + break; + } + + for (i = 4; i >= 0; i--) { + int val = acc % 85; + acc /= 85; + + b85[i] = base85_encode[val]; + } + + for (i = 0; i < 5; i++) + buf->ptr[buf->size++] = b85[i]; + } + + buf->ptr[buf->size] = '\0'; + + return 0; +} + +/* The inverse of base85_encode */ +static const int8_t base85_decode[] = { + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, 63, -1, 64, 65, 66, 67, -1, 68, 69, 70, 71, -1, 72, -1, -1, + 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, -1, 73, 74, 75, 76, 77, + 78, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, + 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, -1, -1, -1, 79, 80, + 81, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, + 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 82, 83, 84, 85, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 +}; + +int git_buf_decode_base85( + git_buf *buf, + const char *base85, + size_t base85_len, + size_t output_len) +{ + size_t orig_size = buf->size, new_size; + + if (base85_len % 5 || + output_len > base85_len * 4 / 5) { + git_error_set(GIT_ERROR_INVALID, "invalid base85 input"); + return -1; + } + + GIT_ERROR_CHECK_ALLOC_ADD(&new_size, output_len, buf->size); + GIT_ERROR_CHECK_ALLOC_ADD(&new_size, new_size, 1); + ENSURE_SIZE(buf, new_size); + + while (output_len) { + unsigned acc = 0; + int de, cnt = 4; + unsigned char ch; + do { + ch = *base85++; + de = base85_decode[ch]; + if (--de < 0) + goto on_error; + + acc = acc * 85 + de; + } while (--cnt); + ch = *base85++; + de = base85_decode[ch]; + if (--de < 0) + goto on_error; + + /* Detect overflow. */ + if (0xffffffff / 85 < acc || + 0xffffffff - de < (acc *= 85)) + goto on_error; + + acc += de; + + cnt = (output_len < 4) ? (int)output_len : 4; + output_len -= cnt; + do { + acc = (acc << 8) | (acc >> 24); + buf->ptr[buf->size++] = acc; + } while (--cnt); + } + + buf->ptr[buf->size] = 0; + + return 0; + +on_error: + buf->size = orig_size; + buf->ptr[buf->size] = '\0'; + + git_error_set(GIT_ERROR_INVALID, "invalid base85 input"); + return -1; +} + +#define HEX_DECODE(c) ((c | 32) % 39 - 9) + +int git_buf_decode_percent( + git_buf *buf, + const char *str, + size_t str_len) +{ + size_t str_pos, new_size; + + GIT_ERROR_CHECK_ALLOC_ADD(&new_size, buf->size, str_len); + GIT_ERROR_CHECK_ALLOC_ADD(&new_size, new_size, 1); + ENSURE_SIZE(buf, new_size); + + for (str_pos = 0; str_pos < str_len; buf->size++, str_pos++) { + if (str[str_pos] == '%' && + str_len > str_pos + 2 && + isxdigit(str[str_pos + 1]) && + isxdigit(str[str_pos + 2])) { + buf->ptr[buf->size] = (HEX_DECODE(str[str_pos + 1]) << 4) + + HEX_DECODE(str[str_pos + 2]); + str_pos += 2; + } else { + buf->ptr[buf->size] = str[str_pos]; + } + } + + buf->ptr[buf->size] = '\0'; + return 0; +} + +int git_buf_vprintf(git_buf *buf, const char *format, va_list ap) +{ + size_t expected_size, new_size; + int len; + + GIT_ERROR_CHECK_ALLOC_MULTIPLY(&expected_size, strlen(format), 2); + GIT_ERROR_CHECK_ALLOC_ADD(&expected_size, expected_size, buf->size); + ENSURE_SIZE(buf, expected_size); + + while (1) { + va_list args; + va_copy(args, ap); + + len = p_vsnprintf( + buf->ptr + buf->size, + buf->asize - buf->size, + format, args + ); + + va_end(args); + + if (len < 0) { + git__free(buf->ptr); + buf->ptr = git_buf__oom; + return -1; + } + + if ((size_t)len + 1 <= buf->asize - buf->size) { + buf->size += len; + break; + } + + GIT_ERROR_CHECK_ALLOC_ADD(&new_size, buf->size, len); + GIT_ERROR_CHECK_ALLOC_ADD(&new_size, new_size, 1); + ENSURE_SIZE(buf, new_size); + } + + return 0; +} + +int git_buf_printf(git_buf *buf, const char *format, ...) +{ + int r; + va_list ap; + + va_start(ap, format); + r = git_buf_vprintf(buf, format, ap); + va_end(ap); + + return r; +} + +void git_buf_copy_cstr(char *data, size_t datasize, const git_buf *buf) +{ + size_t copylen; + + assert(data && datasize && buf); + + data[0] = '\0'; + + if (buf->size == 0 || buf->asize <= 0) + return; + + copylen = buf->size; + if (copylen > datasize - 1) + copylen = datasize - 1; + memmove(data, buf->ptr, copylen); + data[copylen] = '\0'; +} + +void git_buf_consume_bytes(git_buf *buf, size_t len) +{ + git_buf_consume(buf, buf->ptr + len); +} + +void git_buf_consume(git_buf *buf, const char *end) +{ + if (end > buf->ptr && end <= buf->ptr + buf->size) { + size_t consumed = end - buf->ptr; + memmove(buf->ptr, end, buf->size - consumed); + buf->size -= consumed; + buf->ptr[buf->size] = '\0'; + } +} + +void git_buf_truncate(git_buf *buf, size_t len) +{ + if (len >= buf->size) + return; + + buf->size = len; + if (buf->size < buf->asize) + buf->ptr[buf->size] = '\0'; +} + +void git_buf_shorten(git_buf *buf, size_t amount) +{ + if (buf->size > amount) + git_buf_truncate(buf, buf->size - amount); + else + git_buf_clear(buf); +} + +void git_buf_rtruncate_at_char(git_buf *buf, char separator) +{ + ssize_t idx = git_buf_rfind_next(buf, separator); + git_buf_truncate(buf, idx < 0 ? 0 : (size_t)idx); +} + +void git_buf_swap(git_buf *buf_a, git_buf *buf_b) +{ + git_buf t = *buf_a; + *buf_a = *buf_b; + *buf_b = t; +} + +char *git_buf_detach(git_buf *buf) +{ + char *data = buf->ptr; + + if (buf->asize == 0 || buf->ptr == git_buf__oom) + return NULL; + + git_buf_init(buf, 0); + + return data; +} + +int git_buf_attach(git_buf *buf, char *ptr, size_t asize) +{ + git_buf_dispose(buf); + + if (ptr) { + buf->ptr = ptr; + buf->size = strlen(ptr); + if (asize) + buf->asize = (asize < buf->size) ? buf->size + 1 : asize; + else /* pass 0 to fall back on strlen + 1 */ + buf->asize = buf->size + 1; + } + + ENSURE_SIZE(buf, asize); + return 0; +} + +void git_buf_attach_notowned(git_buf *buf, const char *ptr, size_t size) +{ + if (git_buf_is_allocated(buf)) + git_buf_dispose(buf); + + if (!size) { + git_buf_init(buf, 0); + } else { + buf->ptr = (char *)ptr; + buf->asize = 0; + buf->size = size; + } +} + +int git_buf_join_n(git_buf *buf, char separator, int nbuf, ...) +{ + va_list ap; + int i; + size_t total_size = 0, original_size = buf->size; + char *out, *original = buf->ptr; + + if (buf->size > 0 && buf->ptr[buf->size - 1] != separator) + ++total_size; /* space for initial separator */ + + /* Make two passes to avoid multiple reallocation */ + + va_start(ap, nbuf); + for (i = 0; i < nbuf; ++i) { + const char* segment; + size_t segment_len; + + segment = va_arg(ap, const char *); + if (!segment) + continue; + + segment_len = strlen(segment); + + GIT_ERROR_CHECK_ALLOC_ADD(&total_size, total_size, segment_len); + + if (segment_len == 0 || segment[segment_len - 1] != separator) + GIT_ERROR_CHECK_ALLOC_ADD(&total_size, total_size, 1); + } + va_end(ap); + + /* expand buffer if needed */ + if (total_size == 0) + return 0; + + GIT_ERROR_CHECK_ALLOC_ADD(&total_size, total_size, 1); + if (git_buf_grow_by(buf, total_size) < 0) + return -1; + + out = buf->ptr + buf->size; + + /* append separator to existing buf if needed */ + if (buf->size > 0 && out[-1] != separator) + *out++ = separator; + + va_start(ap, nbuf); + for (i = 0; i < nbuf; ++i) { + const char* segment; + size_t segment_len; + + segment = va_arg(ap, const char *); + if (!segment) + continue; + + /* deal with join that references buffer's original content */ + if (segment >= original && segment < original + original_size) { + size_t offset = (segment - original); + segment = buf->ptr + offset; + segment_len = original_size - offset; + } else { + segment_len = strlen(segment); + } + + /* skip leading separators */ + if (out > buf->ptr && out[-1] == separator) + while (segment_len > 0 && *segment == separator) { + segment++; + segment_len--; + } + + /* copy over next buffer */ + if (segment_len > 0) { + memmove(out, segment, segment_len); + out += segment_len; + } + + /* append trailing separator (except for last item) */ + if (i < nbuf - 1 && out > buf->ptr && out[-1] != separator) + *out++ = separator; + } + va_end(ap); + + /* set size based on num characters actually written */ + buf->size = out - buf->ptr; + buf->ptr[buf->size] = '\0'; + + return 0; +} + +int git_buf_join( + git_buf *buf, + char separator, + const char *str_a, + const char *str_b) +{ + size_t strlen_a = str_a ? strlen(str_a) : 0; + size_t strlen_b = strlen(str_b); + size_t alloc_len; + int need_sep = 0; + ssize_t offset_a = -1; + + /* not safe to have str_b point internally to the buffer */ + assert(str_b < buf->ptr || str_b >= buf->ptr + buf->size); + + /* figure out if we need to insert a separator */ + if (separator && strlen_a) { + while (*str_b == separator) { str_b++; strlen_b--; } + if (str_a[strlen_a - 1] != separator) + need_sep = 1; + } + + /* str_a could be part of the buffer */ + if (str_a >= buf->ptr && str_a < buf->ptr + buf->size) + offset_a = str_a - buf->ptr; + + GIT_ERROR_CHECK_ALLOC_ADD(&alloc_len, strlen_a, strlen_b); + GIT_ERROR_CHECK_ALLOC_ADD(&alloc_len, alloc_len, need_sep); + GIT_ERROR_CHECK_ALLOC_ADD(&alloc_len, alloc_len, 1); + ENSURE_SIZE(buf, alloc_len); + + /* fix up internal pointers */ + if (offset_a >= 0) + str_a = buf->ptr + offset_a; + + /* do the actual copying */ + if (offset_a != 0 && str_a) + memmove(buf->ptr, str_a, strlen_a); + if (need_sep) + buf->ptr[strlen_a] = separator; + memcpy(buf->ptr + strlen_a + need_sep, str_b, strlen_b); + + buf->size = strlen_a + strlen_b + need_sep; + buf->ptr[buf->size] = '\0'; + + return 0; +} + +int git_buf_join3( + git_buf *buf, + char separator, + const char *str_a, + const char *str_b, + const char *str_c) +{ + size_t len_a = strlen(str_a), + len_b = strlen(str_b), + len_c = strlen(str_c), + len_total; + int sep_a = 0, sep_b = 0; + char *tgt; + + /* for this function, disallow pointers into the existing buffer */ + assert(str_a < buf->ptr || str_a >= buf->ptr + buf->size); + assert(str_b < buf->ptr || str_b >= buf->ptr + buf->size); + assert(str_c < buf->ptr || str_c >= buf->ptr + buf->size); + + if (separator) { + if (len_a > 0) { + while (*str_b == separator) { str_b++; len_b--; } + sep_a = (str_a[len_a - 1] != separator); + } + if (len_a > 0 || len_b > 0) + while (*str_c == separator) { str_c++; len_c--; } + if (len_b > 0) + sep_b = (str_b[len_b - 1] != separator); + } + + GIT_ERROR_CHECK_ALLOC_ADD(&len_total, len_a, sep_a); + GIT_ERROR_CHECK_ALLOC_ADD(&len_total, len_total, len_b); + GIT_ERROR_CHECK_ALLOC_ADD(&len_total, len_total, sep_b); + GIT_ERROR_CHECK_ALLOC_ADD(&len_total, len_total, len_c); + GIT_ERROR_CHECK_ALLOC_ADD(&len_total, len_total, 1); + ENSURE_SIZE(buf, len_total); + + tgt = buf->ptr; + + if (len_a) { + memcpy(tgt, str_a, len_a); + tgt += len_a; + } + if (sep_a) + *tgt++ = separator; + if (len_b) { + memcpy(tgt, str_b, len_b); + tgt += len_b; + } + if (sep_b) + *tgt++ = separator; + if (len_c) + memcpy(tgt, str_c, len_c); + + buf->size = len_a + sep_a + len_b + sep_b + len_c; + buf->ptr[buf->size] = '\0'; + + return 0; +} + +void git_buf_rtrim(git_buf *buf) +{ + while (buf->size > 0) { + if (!git__isspace(buf->ptr[buf->size - 1])) + break; + + buf->size--; + } + + if (buf->asize > buf->size) + buf->ptr[buf->size] = '\0'; +} + +int git_buf_cmp(const git_buf *a, const git_buf *b) +{ + int result = memcmp(a->ptr, b->ptr, min(a->size, b->size)); + return (result != 0) ? result : + (a->size < b->size) ? -1 : (a->size > b->size) ? 1 : 0; +} + +int git_buf_splice( + git_buf *buf, + size_t where, + size_t nb_to_remove, + const char *data, + size_t nb_to_insert) +{ + char *splice_loc; + size_t new_size, alloc_size; + + assert(buf && where <= buf->size && nb_to_remove <= buf->size - where); + + splice_loc = buf->ptr + where; + + /* Ported from git.git + * https://github.com/git/git/blob/16eed7c/strbuf.c#L159-176 + */ + GIT_ERROR_CHECK_ALLOC_ADD(&new_size, (buf->size - nb_to_remove), nb_to_insert); + GIT_ERROR_CHECK_ALLOC_ADD(&alloc_size, new_size, 1); + ENSURE_SIZE(buf, alloc_size); + + memmove(splice_loc + nb_to_insert, + splice_loc + nb_to_remove, + buf->size - where - nb_to_remove); + + memcpy(splice_loc, data, nb_to_insert); + + buf->size = new_size; + buf->ptr[buf->size] = '\0'; + return 0; +} + +/* Quote per http://marc.info/?l=git&m=112927316408690&w=2 */ +int git_buf_quote(git_buf *buf) +{ + const char whitespace[] = { 'a', 'b', 't', 'n', 'v', 'f', 'r' }; + git_buf quoted = GIT_BUF_INIT; + size_t i = 0; + bool quote = false; + int error = 0; + + /* walk to the first char that needs quoting */ + if (buf->size && buf->ptr[0] == '!') + quote = true; + + for (i = 0; !quote && i < buf->size; i++) { + if (buf->ptr[i] == '"' || buf->ptr[i] == '\\' || + buf->ptr[i] < ' ' || buf->ptr[i] > '~') { + quote = true; + break; + } + } + + if (!quote) + goto done; + + git_buf_putc("ed, '"'); + git_buf_put("ed, buf->ptr, i); + + for (; i < buf->size; i++) { + /* whitespace - use the map above, which is ordered by ascii value */ + if (buf->ptr[i] >= '\a' && buf->ptr[i] <= '\r') { + git_buf_putc("ed, '\\'); + git_buf_putc("ed, whitespace[buf->ptr[i] - '\a']); + } + + /* double quote and backslash must be escaped */ + else if (buf->ptr[i] == '"' || buf->ptr[i] == '\\') { + git_buf_putc("ed, '\\'); + git_buf_putc("ed, buf->ptr[i]); + } + + /* escape anything unprintable as octal */ + else if (buf->ptr[i] != ' ' && + (buf->ptr[i] < '!' || buf->ptr[i] > '~')) { + git_buf_printf("ed, "\\%03o", (unsigned char)buf->ptr[i]); + } + + /* yay, printable! */ + else { + git_buf_putc("ed, buf->ptr[i]); + } + } + + git_buf_putc("ed, '"'); + + if (git_buf_oom("ed)) { + error = -1; + goto done; + } + + git_buf_swap("ed, buf); + +done: + git_buf_dispose("ed); + return error; +} + +/* Unquote per http://marc.info/?l=git&m=112927316408690&w=2 */ +int git_buf_unquote(git_buf *buf) +{ + size_t i, j; + char ch; + + git_buf_rtrim(buf); + + if (buf->size < 2 || buf->ptr[0] != '"' || buf->ptr[buf->size-1] != '"') + goto invalid; + + for (i = 0, j = 1; j < buf->size-1; i++, j++) { + ch = buf->ptr[j]; + + if (ch == '\\') { + if (j == buf->size-2) + goto invalid; + + ch = buf->ptr[++j]; + + switch (ch) { + /* \" or \\ simply copy the char in */ + case '"': case '\\': + break; + + /* add the appropriate escaped char */ + case 'a': ch = '\a'; break; + case 'b': ch = '\b'; break; + case 'f': ch = '\f'; break; + case 'n': ch = '\n'; break; + case 'r': ch = '\r'; break; + case 't': ch = '\t'; break; + case 'v': ch = '\v'; break; + + /* \xyz digits convert to the char*/ + case '0': case '1': case '2': case '3': + if (j == buf->size-3) { + git_error_set(GIT_ERROR_INVALID, + "truncated quoted character \\%c", ch); + return -1; + } + + if (buf->ptr[j+1] < '0' || buf->ptr[j+1] > '7' || + buf->ptr[j+2] < '0' || buf->ptr[j+2] > '7') { + git_error_set(GIT_ERROR_INVALID, + "truncated quoted character \\%c%c%c", + buf->ptr[j], buf->ptr[j+1], buf->ptr[j+2]); + return -1; + } + + ch = ((buf->ptr[j] - '0') << 6) | + ((buf->ptr[j+1] - '0') << 3) | + (buf->ptr[j+2] - '0'); + j += 2; + break; + + default: + git_error_set(GIT_ERROR_INVALID, "invalid quoted character \\%c", ch); + return -1; + } + } + + buf->ptr[i] = ch; + } + + buf->ptr[i] = '\0'; + buf->size = i; + + return 0; + +invalid: + git_error_set(GIT_ERROR_INVALID, "invalid quoted line"); + return -1; +} |