diff options
Diffstat (limited to 'source/pdf/pdf-link.c')
-rw-r--r-- | source/pdf/pdf-link.c | 356 |
1 files changed, 356 insertions, 0 deletions
diff --git a/source/pdf/pdf-link.c b/source/pdf/pdf-link.c new file mode 100644 index 00000000..56c11973 --- /dev/null +++ b/source/pdf/pdf-link.c @@ -0,0 +1,356 @@ +#include "mupdf/fitz.h" +#include "mupdf/pdf.h" + +#include <string.h> + +static pdf_obj * +resolve_dest_rec(fz_context *ctx, pdf_document *doc, pdf_obj *dest, int depth) +{ + if (depth > 10) /* Arbitrary to avoid infinite recursion */ + return NULL; + + if (pdf_is_name(ctx, dest) || pdf_is_string(ctx, dest)) + { + dest = pdf_lookup_dest(ctx, doc, dest); + dest = resolve_dest_rec(ctx, doc, dest, depth+1); + return dest; + } + + else if (pdf_is_array(ctx, dest)) + { + return dest; + } + + else if (pdf_is_dict(ctx, dest)) + { + dest = pdf_dict_get(ctx, dest, PDF_NAME(D)); + return resolve_dest_rec(ctx, doc, dest, depth+1); + } + + else if (pdf_is_indirect(ctx, dest)) + return dest; + + return NULL; +} + +static pdf_obj * +resolve_dest(fz_context *ctx, pdf_document *doc, pdf_obj *dest) +{ + return resolve_dest_rec(ctx, doc, dest, 0); +} + +char * +pdf_parse_link_dest(fz_context *ctx, pdf_document *doc, pdf_obj *dest) +{ + pdf_obj *obj; + char buf[256]; + const char *ld; + int page; + int x, y; + + dest = resolve_dest(ctx, doc, dest); + if (dest == NULL) + { + fz_warn(ctx, "undefined link destination"); + return NULL; + } + + if (pdf_is_name(ctx, dest)) + { + ld = pdf_to_name(ctx, dest); + return fz_strdup(ctx, ld); + } + else if (pdf_is_string(ctx, dest)) + { + ld = pdf_to_str_buf(ctx, dest); + return fz_strdup(ctx, ld); + } + + obj = pdf_array_get(ctx, dest, 0); + if (pdf_is_int(ctx, obj)) + page = pdf_to_int(ctx, obj); + else + { + fz_try(ctx) + page = pdf_lookup_page_number(ctx, doc, obj); + fz_catch(ctx) + page = -1; + } + + x = y = 0; + obj = pdf_array_get(ctx, dest, 1); + if (pdf_name_eq(ctx, obj, PDF_NAME(XYZ))) + { + x = pdf_array_get_int(ctx, dest, 2); + y = pdf_array_get_int(ctx, dest, 3); + } + else if (pdf_name_eq(ctx, obj, PDF_NAME(FitR))) + { + x = pdf_array_get_int(ctx, dest, 2); + y = pdf_array_get_int(ctx, dest, 5); + } + else if (pdf_name_eq(ctx, obj, PDF_NAME(FitH)) || pdf_name_eq(ctx, obj, PDF_NAME(FitBH))) + y = pdf_array_get_int(ctx, dest, 2); + else if (pdf_name_eq(ctx, obj, PDF_NAME(FitV)) || pdf_name_eq(ctx, obj, PDF_NAME(FitBV))) + x = pdf_array_get_int(ctx, dest, 2); + + if (page >= 0) + { + if (x != 0 || y != 0) + fz_snprintf(buf, sizeof buf, "#%d,%d,%d", page + 1, x, y); + else + fz_snprintf(buf, sizeof buf, "#%d", page + 1); + return fz_strdup(ctx, buf); + } + + return NULL; +} + +char * +pdf_parse_file_spec(fz_context *ctx, pdf_document *doc, pdf_obj *file_spec, pdf_obj *dest) +{ + pdf_obj *filename=NULL; + char *path = NULL; + char *uri = NULL; + char buf[256]; + size_t n; + + if (pdf_is_string(ctx, file_spec)) + filename = file_spec; + + if (pdf_is_dict(ctx, file_spec)) { +#ifdef _WIN32 + filename = pdf_dict_get(ctx, file_spec, PDF_NAME(DOS)); +#else + filename = pdf_dict_get(ctx, file_spec, PDF_NAME(Unix)); +#endif + if (!filename) + filename = pdf_dict_geta(ctx, file_spec, PDF_NAME(UF), PDF_NAME(F)); + } + + if (!pdf_is_string(ctx, filename)) + { + fz_warn(ctx, "cannot parse file specification"); + return NULL; + } + + path = pdf_to_utf8(ctx, filename); +#ifdef _WIN32 + if (!pdf_name_eq(ctx, pdf_dict_get(ctx, file_spec, PDF_NAME(FS)), PDF_NAME(URL))) + { + /* move the file name into the expected place and use the expected path separator */ + char *c; + if (path[0] == '/' && (('A' <= path[1] && path[1] <= 'Z') || ('a' <= path[1] && path[1] <= 'z')) && path[2] == '/') + { + path[0] = path[1]; + path[1] = ':'; + } + for (c = path; *c; c++) + { + if (*c == '/') + *c = '\\'; + } + } +#endif + + if (pdf_is_array(ctx, dest)) + fz_snprintf(buf, sizeof buf, "#page=%d", pdf_array_get_int(ctx, dest, 0) + 1); + else if (pdf_is_name(ctx, dest)) + fz_snprintf(buf, sizeof buf, "#%s", pdf_to_name(ctx, dest)); + else if (pdf_is_string(ctx, dest)) + fz_snprintf(buf, sizeof buf, "#%s", pdf_to_str_buf(ctx, dest)); + else + buf[0] = 0; + + n = 7 + strlen(path) + strlen(buf) + 1; + uri = fz_malloc(ctx, n); + fz_strlcpy(uri, "file://", n); + fz_strlcat(uri, path, n); + fz_strlcat(uri, buf, n); + fz_free(ctx, path); + return uri; +} + +char * +pdf_parse_link_action(fz_context *ctx, pdf_document *doc, pdf_obj *action, int pagenum) +{ + pdf_obj *obj, *dest, *file_spec; + + if (!action) + return NULL; + + obj = pdf_dict_get(ctx, action, PDF_NAME(S)); + if (pdf_name_eq(ctx, PDF_NAME(GoTo), obj)) + { + dest = pdf_dict_get(ctx, action, PDF_NAME(D)); + return pdf_parse_link_dest(ctx, doc, dest); + } + else if (pdf_name_eq(ctx, PDF_NAME(URI), obj)) + { + /* URI entries are ASCII strings */ + const char *uri = pdf_dict_get_string(ctx, action, PDF_NAME(URI), NULL); + if (!fz_is_external_link(ctx, uri)) + { + pdf_obj *uri_base_obj = pdf_dict_getp(ctx, pdf_trailer(ctx, doc), "Root/URI/Base"); + const char *uri_base = uri_base_obj ? pdf_to_str_buf(ctx, uri_base_obj) : "file://"; + char *new_uri = fz_malloc(ctx, strlen(uri_base) + strlen(uri) + 1); + strcpy(new_uri, uri_base); + strcat(new_uri, uri); + return new_uri; + } + return fz_strdup(ctx, uri); + } + else if (pdf_name_eq(ctx, PDF_NAME(Launch), obj)) + { + file_spec = pdf_dict_get(ctx, action, PDF_NAME(F)); + return pdf_parse_file_spec(ctx, doc, file_spec, NULL); + } + else if (pdf_name_eq(ctx, PDF_NAME(GoToR), obj)) + { + dest = pdf_dict_get(ctx, action, PDF_NAME(D)); + file_spec = pdf_dict_get(ctx, action, PDF_NAME(F)); + return pdf_parse_file_spec(ctx, doc, file_spec, dest); + } + else if (pdf_name_eq(ctx, PDF_NAME(Named), obj)) + { + dest = pdf_dict_get(ctx, action, PDF_NAME(N)); + + if (pdf_name_eq(ctx, PDF_NAME(FirstPage), dest)) + pagenum = 0; + else if (pdf_name_eq(ctx, PDF_NAME(LastPage), dest)) + pagenum = pdf_count_pages(ctx, doc) - 1; + else if (pdf_name_eq(ctx, PDF_NAME(PrevPage), dest) && pagenum >= 0) + { + if (pagenum > 0) + pagenum--; + } + else if (pdf_name_eq(ctx, PDF_NAME(NextPage), dest) && pagenum >= 0) + { + if (pagenum < pdf_count_pages(ctx, doc) - 1) + pagenum++; + } + else + return NULL; + + return fz_asprintf(ctx, "#%d", pagenum + 1); + } + + return NULL; +} + +static fz_link * +pdf_load_link(fz_context *ctx, pdf_document *doc, pdf_obj *dict, int pagenum, const fz_matrix *page_ctm) +{ + pdf_obj *action; + pdf_obj *obj; + fz_rect bbox; + char *uri; + fz_link *link = NULL; + + obj = pdf_dict_get(ctx, dict, PDF_NAME(Subtype)); + if (!pdf_name_eq(ctx, obj, PDF_NAME(Link))) + return NULL; + + obj = pdf_dict_get(ctx, dict, PDF_NAME(Rect)); + if (!obj) + return NULL; + + pdf_to_rect(ctx, obj, &bbox); + fz_transform_rect(&bbox, page_ctm); + + obj = pdf_dict_get(ctx, dict, PDF_NAME(Dest)); + if (obj) + uri = pdf_parse_link_dest(ctx, doc, obj); + else + { + action = pdf_dict_get(ctx, dict, PDF_NAME(A)); + /* fall back to additional action button's down/up action */ + if (!action) + action = pdf_dict_geta(ctx, pdf_dict_get(ctx, dict, PDF_NAME(AA)), PDF_NAME(U), PDF_NAME(D)); + uri = pdf_parse_link_action(ctx, doc, action, pagenum); + } + + if (!uri) + return NULL; + + fz_try(ctx) + link = fz_new_link(ctx, &bbox, doc, uri); + fz_always(ctx) + fz_free(ctx, uri); + fz_catch(ctx) + fz_rethrow(ctx); + + return link; +} + +fz_link * +pdf_load_link_annots(fz_context *ctx, pdf_document *doc, pdf_obj *annots, int pagenum, const fz_matrix *page_ctm) +{ + fz_link *link, *head, *tail; + pdf_obj *obj; + int i, n; + + head = tail = NULL; + link = NULL; + + n = pdf_array_len(ctx, annots); + for (i = 0; i < n; i++) + { + /* FIXME: Move the try/catch out of the loop for performance? */ + fz_try(ctx) + { + obj = pdf_array_get(ctx, annots, i); + link = pdf_load_link(ctx, doc, obj, pagenum, page_ctm); + } + fz_catch(ctx) + { + fz_rethrow_if(ctx, FZ_ERROR_TRYLATER); + link = NULL; + } + + if (link) + { + if (!head) + head = tail = link; + else + { + tail->next = link; + tail = link; + } + } + } + + return head; +} + +int +pdf_resolve_link(fz_context *ctx, pdf_document *doc, const char *uri, float *xp, float *yp) +{ + if (uri && uri[0] == '#') + { + int page = fz_atoi(uri + 1) - 1; + if (xp || yp) + { + const char *x = strchr(uri, ','); + const char *y = strrchr(uri, ','); + if (x && y) + { + pdf_obj *obj; + fz_matrix ctm; + fz_point p; + + p.x = x ? fz_atoi(x + 1) : 0; + p.y = y ? fz_atoi(y + 1) : 0; + obj = pdf_lookup_page_obj(ctx, doc, page); + pdf_page_obj_transform(ctx, obj, NULL, &ctm); + fz_transform_point(&p, &ctm); + + if (xp) *xp = p.x; + if (yp) *yp = p.y; + } + } + return page; + } + fz_warn(ctx, "unknown link uri '%s'", uri); + return -1; +} |