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| -rw-r--r-- | bin/edi.c | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/bin/edi.c b/bin/edi.c new file mode 100644 index 00000000..c53245f0 --- /dev/null +++ b/bin/edi.c @@ -0,0 +1,186 @@ +/* Copyright (C) 2018 Curtis McEnroe <june@causal.agency> + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU Affero General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU Affero General Public License for more details. + * + * You should have received a copy of the GNU Affero General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <curses.h> +#include <err.h> +#include <fcntl.h> +#include <locale.h> +#include <stdio.h> +#include <stdlib.h> +#include <sys/mman.h> +#include <sys/stat.h> +#include <sysexits.h> +#include <unistd.h> + +struct Span { + char *ptr; + size_t len; +}; + +static struct Span spanBefore(struct Span span, size_t index) { + return (struct Span) { span.ptr, index }; +} +static struct Span spanAfter(struct Span span, size_t index) { + return (struct Span) { span.ptr + index, span.len - index }; +} + +static struct Table { + struct Table *next; + struct Table *prev; + size_t len; + struct Span span[]; +} *table; + +static struct Table *tableNew(size_t cap) { + struct Table *next = malloc(sizeof(*next) + cap * sizeof(struct Span)); + if (!next) err(EX_OSERR, "malloc"); + next->next = NULL; + next->prev = NULL; + next->len = 0; + return next; +} + +static struct Table *tableSpan(struct Span span) { + struct Table *next = tableNew(1); + next->len = 1; + next->span[0] = span; + return next; +} + +static void tableUndo(void) { + if (table->prev) table = table->prev; +} +static void tableRedo(void) { + if (table->next) table = table->next; +} + +static void tableDiscard(void) { + struct Table *it = table->next; + table->next = NULL; + while (it) { + struct Table *next = it->next; + free(it); + it = next; + } +} + +static void tablePush(struct Table *next) { + tableDiscard(); + table->next = next; + next->prev = table; + table = next; +} + +static struct Span *tableInsert(size_t atStart, struct Span span) { + // TODO: Handle table->len == 0 + struct Table *next = tableNew(table->len + 2); + struct Span *insert = NULL; + + size_t start = 0; + struct Span *nextSpan = next->span; + for (size_t i = 0; i < table->len; ++i) { + struct Span prevSpan = table->span[i]; + size_t end = start + prevSpan.len; + + if (atStart > start && atStart < end) { + insert = nextSpan + 1; + *nextSpan++ = spanBefore(prevSpan, atStart - start); + *nextSpan++ = span; + *nextSpan++ = spanAfter(prevSpan, atStart - start); + } else if (atStart == start) { + insert = nextSpan; + *nextSpan++ = span; + *nextSpan++ = prevSpan; + } else { + *nextSpan++ = prevSpan; + } + + start = end; + } + next->len = nextSpan - next->span; + + tablePush(next); + return insert; +} + +static void tableDelete(size_t atStart, size_t atEnd) { + struct Table *next = tableNew(table->len + 1); + + size_t start = 0; + struct Span *nextSpan = next->span; + for (size_t i = 0; i < table->len; ++i) { + struct Span prevSpan = table->span[i]; + size_t end = start + prevSpan.len; + + if (atStart > start && atEnd < end) { + *nextSpan++ = spanBefore(prevSpan, atStart - start); + *nextSpan++ = spanAfter(prevSpan, atEnd - start); + } else if (atStart > start && atStart < end && atEnd >= end) { + *nextSpan++ = spanBefore(prevSpan, atStart - start); + } else if (atStart <= start && atEnd < end && atEnd > start) { + *nextSpan++ = spanAfter(prevSpan, atEnd - start); + } else if (atStart <= start && atEnd >= end) { + } else { + *nextSpan++ = prevSpan; + } + + start = end; + } + next->len = nextSpan - next->span; + + tablePush(next); +} + +static void curse(void) { + setlocale(LC_CTYPE, ""); + initscr(); + cbreak(); + noecho(); + keypad(stdscr, true); + set_escdelay(100); +} + +static void draw(void) { + move(0, 0); + for (size_t i = 0; i < table->len; ++i) { + addnstr(table->span[i].ptr, (int)table->span[i].len); + } +} + +int main(int argc, char *argv[]) { + if (argc < 2) return EX_USAGE; + + const char *path = argv[1]; + int fd = open(path, O_RDWR | O_CREAT, 0644); + if (fd < 0) err(EX_CANTCREAT, "%s", path); + + struct stat stat; + int error = fstat(fd, &stat); + if (error) err(EX_IOERR, "%s", path); + + if (stat.st_size) { + char *file = mmap(NULL, stat.st_size, PROT_READ, MAP_PRIVATE, fd, 0); + if (file == MAP_FAILED) err(EX_IOERR, "%s", path); + table = tableSpan((struct Span) { file, stat.st_size }); + } else { + table = tableSpan((struct Span) { NULL, 0 }); + } + + curse(); + draw(); + getch(); + endwin(); +} |