diff options
| -rw-r--r-- | text.c | 37 |
1 files changed, 34 insertions, 3 deletions
@@ -35,6 +35,10 @@ #include "util.h" #define BUFFER_SIZE (1 << 20) +/* Files smaller than this value are copied on load, larger ones are mmap(2)-ed + * directely. Hence the former can be truncated, while doing so on the latter + * results in havoc. */ +#define BUFFER_MMAP_SIZE (1 << 23) struct Regex { const char *string; @@ -136,6 +140,7 @@ struct Text { /* buffer management */ static Buffer *buffer_alloc(Text *txt, size_t size); +static Buffer *buffer_read(Text *txt, size_t size, int fd); static Buffer *buffer_mmap(Text *txt, size_t size, int fd, off_t offset); static void buffer_free(Buffer *buf); static bool buffer_capacity(Buffer *buf, size_t len); @@ -203,6 +208,27 @@ static Buffer *buffer_alloc(Text *txt, size_t size) { return buf; } +static Buffer *buffer_read(Text *txt, size_t size, int fd) { + Buffer *buf = buffer_alloc(txt, size); + if (!buf) + return NULL; + while (size > 0) { + char data[4096]; + ssize_t len = read(fd, data, MIN(sizeof(data), size)); + if (len == -1) { + txt->buffers = buf->next; + buffer_free(buf); + return NULL; + } else if (len == 0) { + break; + } else { + buffer_append(buf, data, len); + size -= len; + } + } + return buf; +} + static Buffer *buffer_mmap(Text *txt, size_t size, int fd, off_t offset) { Buffer *buf = calloc(1, sizeof(Buffer)); if (!buf) @@ -993,15 +1019,20 @@ Text *text_load(const char *filename) { goto out; } // XXX: use lseek(fd, 0, SEEK_END); instead? - if (!(txt->buf = buffer_mmap(txt, txt->info.st_size, txt->fd, 0))) + size_t size = txt->info.st_size; + if (size < BUFFER_MMAP_SIZE) + txt->buf = buffer_read(txt, size, txt->fd); + else + txt->buf = buffer_mmap(txt, size, txt->fd, 0); + if (!txt->buf) goto out; Piece *p = piece_alloc(txt); if (!p) goto out; piece_init(&txt->begin, NULL, p, NULL, 0); - piece_init(p, &txt->begin, &txt->end, txt->buf->data, txt->buf->size); + piece_init(p, &txt->begin, &txt->end, txt->buf->data, txt->buf->len); piece_init(&txt->end, p, NULL, NULL, 0); - txt->size = txt->buf->size; + txt->size = txt->buf->len; } /* write an empty action */ change_alloc(txt, EPOS); |