Renaming files: printing->print, file_loader->files

1 files changed, 384 insertions, 0 deletions

diff --git a/print.c b/print.c
new file mode 100644
index 0000000..6feee3f
--- /dev/null
+++ b/print.c
@@ -0,0 +1,384 @@
+//
+// print.c - Code for printing and visualizing matches.
+//
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "print.h"
+#include "types.h"
+#include "utils.h"
+#include "vm.h"
+
+typedef struct match_node_s {
+    match_t *m;
+    struct match_node_s *next;
+} match_node_t;
+
+static const char *color_match = "\033[0;31;1m";
+static const char *color_replace = "\033[0;34;1m";
+static const char *color_normal = "\033[0m";
+
+__attribute__((nonnull, pure))
+static int height_of_match(match_t *m);
+__attribute__((nonnull))
+static void _visualize_matches(match_node_t *firstmatch, int depth, const char *text, size_t textlen);
+__attribute__((nonnull(1,2)))
+static inline void print_line_number(FILE *out, printer_t *pr, size_t line_number, const char *color);
+
+//
+// Return the height of a match object (i.e. the number of descendents of the
+// structure).
+//
+static int height_of_match(match_t *m)
+{
+    int height = 0;
+    for (match_t *c = m->child; c; c = c->nextsibling) {
+        int childheight = height_of_match(c);
+        if (childheight > height) height = childheight;
+    }
+    return 1 + height;
+}
+
+//
+// Print a visual explanation for the as-yet-unprinted matches provided.
+//
+static void _visualize_matches(match_node_t *firstmatch, int depth, const char *text, size_t textlen)
+{
+    const char *V = "│"; // Vertical bar
+    const char *H = "─"; // Horizontal bar
+    const char *color = (depth % 2 == 0) ? "34" : "33";
+
+    match_t *viz = firstmatch->m;
+    // This is a heuristic: print matches first if they have more submatches.
+    // In general, this helps reduce the height of the final output by allowing
+    // for more rows that show the same rule matching in multiple places.
+    // TODO: there may be a better heuristic that optimizes for this factor
+    // while also printing earlier matches first when it doesn't affect overall
+    // output height.
+    for (match_node_t *p = firstmatch; p; p = p->next)
+        if (height_of_match(p->m) > height_of_match(viz))
+            viz = p->m;
+    const char *viz_type = viz->pat->start;
+    size_t viz_typelen = (size_t)(viz->pat->end - viz->pat->start);
+
+    // Backrefs use added dim quote marks to indicate that the pattern is a
+    // literal string being matched. (Backrefs have start/end inside the text
+    // input, instead of something the user typed in)
+    if (viz_type >= text && viz_type <= &text[textlen])
+        printf("\033[%ldG\033[0;2m\"\033[%s;1m", 2*textlen+3, color);
+    else
+        printf("\033[%ldG\033[%s;1m", 2*textlen+3, color);
+
+    for (size_t i = 0; i < viz_typelen; i++) {
+        switch (viz_type[i]) {
+            case '\n': printf("↵"); break;
+            default: printf("%c", viz_type[i]); break;
+        }
+    }
+
+    if (viz_type >= text && viz_type <= &text[textlen])
+        printf("\033[0;2m\"");
+
+    printf("\033[0m");
+
+    match_node_t *children = NULL;
+    match_node_t **nextchild = &children;
+
+#define RIGHT_TYPE(m) (m->m->pat->end == m->m->pat->start + viz_typelen && strncmp(m->m->pat->start, viz_type, viz_typelen) == 0)
+    // Print nonzero-width first:
+    for (match_node_t *m = firstmatch; m; m = m->next) {
+        if (RIGHT_TYPE(m)) {
+            for (match_t *c = m->m->child; c; c = c->nextsibling) {
+                *nextchild = new(match_node_t);
+                (*nextchild)->m = c;
+                nextchild = &((*nextchild)->next);
+            }
+            if (m->m->end == m->m->start) continue;
+            printf("\033[%ldG\033[0;2m%s\033[0;7;%sm", 1+2*(m->m->start - text), V, color);
+            for (const char *c = m->m->start; c < m->m->end; ++c) {
+                // TODO: newline
+                if (c > m->m->start) printf(" ");
+                // TODO: utf8
+                //while ((*c & 0xC0) != 0x80) printf("%c", *(c++));
+                printf("%c", *c);
+            }
+            printf("\033[0;2m%s\033[0m", V);
+        } else {
+            *nextchild = new(match_node_t);
+            (*nextchild)->m = m->m;
+            nextchild = &((*nextchild)->next);
+            printf("\033[%ldG\033[0;2m%s", 1+2*(m->m->start - text), V);
+            for (ssize_t i = (ssize_t)(2*(m->m->end - m->m->start)-1); i > 0; i--)
+                printf(" ");
+            if (m->m->end > m->m->start)
+                printf("\033[0;2m%s", V);
+            printf("\033[0m");
+        }
+    }
+
+    // Print stars for zero-width:
+    for (match_node_t *m = firstmatch; m; m = m->next) {
+        if (m->m->end > m->m->start) continue;
+        if (RIGHT_TYPE(m)) {
+            printf("\033[%ldG\033[7;%sm▒\033[0m", 1+2*(m->m->start - text), color);
+        } else {
+            printf("\033[%ldG\033[0;2m%s\033[0m", 1+2*(m->m->start - text), V);
+        }
+    }
+
+    printf("\n");
+
+    for (match_node_t *m = firstmatch; m; m = m->next) {
+        if (m->m->end == m->m->start) {
+            if (!RIGHT_TYPE(m))
+                printf("\033[%ldG\033[0;2m%s", 1 + 2*(m->m->start - text), V);
+        } else {
+            const char *l = "└";
+            const char *r = "┘";
+            for (match_node_t *c = children; c; c = c->next) {
+                if (c->m->start == m->m->start || c->m->end == m->m->start) l = V;
+                if (c->m->start == m->m->end   || c->m->end == m->m->end) r = V;
+            }
+            printf("\033[%ldG\033[0;2m%s", 1 + 2*(m->m->start - text), l);
+            const char *h = RIGHT_TYPE(m) ? H : " ";
+            for (ssize_t n = (ssize_t)(2*(m->m->end - m->m->start) - 1); n > 0; n--)
+                printf("%s", h);
+            printf("%s\033[0m", r);
+        }
+    }
+#undef RIGHT_TYPE
+
+    printf("\n");
+
+    if (children)
+        _visualize_matches(children, depth+1, text, textlen);
+
+    for (match_node_t *c = children, *next = NULL; c; c = next) {
+        next = c->next;
+        xfree(&c);
+    }
+}
+
+//
+// Print a visualization of a match object.
+//
+void visualize_match(match_t *m)
+{
+    printf("\033[?7l"); // Disable line wrapping
+    match_node_t first = {.m = m};
+    _visualize_matches(&first, 0, m->start, (size_t)(m->end - m->start));
+    printf("\033[?7h"); // Re-enable line wrapping
+}
+
+//
+// Print a line number, if it needs to be printed.
+// line number of 0 means "just print an empty space for the number"
+//
+__attribute__((nonnull(1,2)))
+static inline void print_line_number(FILE *out, printer_t *pr, size_t line_number, const char *color)
+{
+    if (!pr->print_line_numbers) return;
+    if (!pr->needs_line_number) return;
+    if (line_number == 0) {
+        if (color) fprintf(out, "\033[0;2m     \033(0\x78\033(B%s", color);
+        else fprintf(out, "     |");
+    } else {
+        if (color) fprintf(out, "\033[0;2m% 5ld\033(0\x78\033(B%s", line_number, color);
+        else fprintf(out, "% 5ld|", line_number);
+    }
+    pr->needs_line_number = 0;
+}
+
+// 
+// Print a range of text from a file, adding line numbers if necessary.
+//
+__attribute__((nonnull(1,2,3,4)))
+static void print_between(FILE *out, printer_t *pr, const char *start, const char *end, const char *color)
+{
+    file_t *f = pr->file;
+    while (start < end) {
+        size_t line_num = get_line_number(f, start);
+        print_line_number(out, pr, line_num, color);
+        const char *eol = get_line(pr->file, line_num + 1);
+        if (!eol || eol > end) eol = end;
+        if (color) fprintf(out, "%s", color);
+        fprintf(out, "%.*s", (int)(eol - start), start);
+        if (eol[-1] == '\n')
+            pr->needs_line_number = 1;
+        start = eol;
+    }
+    pr->pos = end;
+}
+
+//
+// Return a pointer to the first character of context information before `pos`,
+// according to the context settings in `pr`
+//
+static const char *context_before(printer_t *pr, const char *pos)
+{
+    if (pr->context_lines == -1) {
+        return pr->pos;
+    } else if (pr->context_lines > 0) {
+        size_t n = get_line_number(pr->file, pos);
+        if (n >= (size_t)((pr->context_lines - 1) + 1))
+            n -= (size_t)(pr->context_lines - 1);
+        else
+            n = 1;
+        const char *sol = get_line(pr->file, n);
+        if (sol == NULL || sol < pr->pos) sol = pr->pos;
+        return sol;
+    } else {
+        return pos;
+    }
+}
+
+//
+// Return a pointer to the last character of context information after `pos`,
+// according to the context settings in `pr`
+//
+static const char *context_after(printer_t *pr, const char *pos)
+{
+    if (pr->context_lines == -1) {
+        return pr->file->end;
+    } else if (pr->context_lines > 0) {
+        size_t n = get_line_number(pr->file, pos) + (size_t)(pr->context_lines - 1);
+        const char *eol = get_line(pr->file, n+1);
+        return eol ? eol : pr->file->end;
+    } else {
+        return pos;
+    }
+}
+
+//
+// Print the text of a match (no context).
+//
+void _print_match(FILE *out, printer_t *pr, match_t *m)
+{
+    pr->pos = m->start;
+    if (m->pat->type == VM_REPLACE) {
+        if (m->skip_replacement) {
+            _print_match(out, pr, m->child);
+            return;
+        }
+        size_t line_start = get_line_number(pr->file, m->start);
+        size_t line_end = get_line_number(pr->file, m->end);
+        size_t line = line_start;
+
+        if (pr->use_color) fprintf(out, "%s", color_replace);
+        const char *text = m->pat->args.replace.text;
+        const char *end = &text[m->pat->args.replace.len];
+
+        // TODO: clean up the line numbering code
+        for (const char *r = text; r < end; ) {
+            print_line_number(out, pr, line > line_end ? 0 : line, pr->use_color ? color_replace : NULL);
+
+            // Capture substitution
+            if (*r == '@' && r[1] && r[1] != '@') {
+                ++r;
+                match_t *cap = get_capture(m, &r);
+                if (cap != NULL) {
+                    _print_match(out, pr, cap);
+                    if (pr->use_color) fprintf(out, "%s", color_replace);
+                    continue;
+                } else {
+                    --r;
+                }
+            }
+
+            if (*r == '\\') {
+                ++r;
+                unsigned char c = unescapechar(r, &r);
+                fputc(c, out);
+                if (c == '\n') {
+                    ++line;
+                    pr->needs_line_number = 1;
+                }
+                continue;
+            } else if (*r == '\n') {
+                fputc('\n', out);
+                ++line;
+                pr->needs_line_number = 1;
+                ++r;
+                continue;
+            } else {
+                fputc(*r, out);
+                ++r;
+                continue;
+            }
+        }
+        print_line_number(out, pr, line > line_end ? 0 : line, pr->use_color ? color_normal : NULL);
+    } else {
+        const char *prev = m->start;
+        for (match_t *child = m->child; child; child = child->nextsibling) {
+            // Skip children from e.g. zero-width matches like >@foo
+            if (!(prev <= child->start && child->start <= m->end &&
+                  prev <= child->end && child->end <= m->end))
+                continue;
+            if (child->start > prev)
+                print_between(out, pr, prev, child->start, pr->use_color ? color_match : NULL);
+            _print_match(out, pr, child);
+            prev = child->end;
+        }
+        if (m->end > prev)
+            print_between(out, pr, prev, m->end, pr->use_color ? color_match : NULL);
+    }
+    pr->pos = m->end;
+}
+
+//
+// Print the text of a match and any context.
+//
+void print_match(FILE *out, printer_t *pr, match_t *m)
+{
+    int first = (pr->pos == NULL);
+    if (first) { // First match printed:
+        pr->pos = pr->file->contents;
+        pr->needs_line_number = 1;
+    }
+    if (m) {
+        const char *before_m = context_before(pr, m->start);
+        if (!first) {
+            const char *after_last = context_after(pr, pr->pos);
+            if (after_last >= before_m) {
+                // Overlapping ranges:
+                before_m = pr->pos;
+            } else {
+                // Non-overlapping ranges:
+                print_between(out, pr, pr->pos, after_last, pr->use_color ? color_normal : NULL);
+                if (pr->context_lines > 1)
+                    fprintf(out, "\n"); // Gap between chunks
+            }
+        }
+        print_between(out, pr, before_m, m->start, pr->use_color ? color_normal : NULL);
+        _print_match(out, pr, m);
+    } else {
+        // After the last match is printed, print the trailing context:
+        const char *after_last = context_after(pr, pr->pos);
+        print_between(out, pr, pr->pos, after_last, pr->use_color ? color_normal : NULL);
+        // Guarantee trailing newline
+        if (pr->pos > pr->file->contents && pr->pos[-1] != '\n') fprintf(out, "\n");
+    }
+    if (pr->use_color) fprintf(out, "%s", color_normal);
+}
+
+//
+// Print any errors that are present in the given match object.
+//
+int print_errors(printer_t *pr, match_t *m)
+{
+    int ret = 0;
+    if (m->pat->type == VM_CAPTURE && m->pat->args.capture.name && streq(m->pat->args.capture.name, "!")) {
+        printf("\033[31;1m");
+        print_match(stdout, pr, m);
+        printf("\033[0m\n");
+        fprint_line(stdout, pr->file, m->start, m->end, " ");
+        return 1;
+    }
+    if (m->child) ret += print_errors(pr, m->child);
+    if (m->nextsibling) ret += print_errors(pr, m->nextsibling);
+    return ret;
+}
+
+// vim: ts=4 sw=0 et cino=L2,l1,(0,W4,m1