pdftool.c

来自「SumatraPDF是一款小型开源的pdf阅读工具。虽然玲珑小巧（只有800多K」· C语言 代码 · 共 1,217 行 · 第 1/2 页

/*
 * Swiss army knife for manipulating and debugging PDFs.
 *
 * There are a few major modes of operation:
 *
 *   show -- pretty-print objects and streams
 *   draw -- render pages to bitmap
 *   clean -- simple rewrite of pdf file
 *   edit -- edit pages (impose and copy operations)
 */

#include "fitz.h"
#include "mupdf.h"

#ifdef _MSC_VER
#include <winsock2.h>
#else
#include <sys/time.h>
#endif

/* put these up here so we can clean up in die() */
fz_renderer *drawgc = nil;
void closesrc(void);

/*
 * Common operations.
 * Parse page selectors.
 * Load and decrypt a PDF file.
 * Select pages.
 */

char *srcname = "(null)";
pdf_xref *src = nil;
pdf_outline *srcoutline = nil;
pdf_pagetree *srcpages = nil;

void die(fz_error *eo)
{
	fflush(stdout);
	fz_printerror(eo);
	fz_droperror(eo);
	fflush(stderr);
	if (drawgc)
		fz_droprenderer(drawgc);
	closesrc();
	abort();
}

void closesrc(void)
{
	if (srcpages)
	{
		pdf_droppagetree(srcpages);
		srcpages = nil;
	}

	if (src)
	{
		if (src->store)
		{
			pdf_dropstore(src->store);
			src->store = nil;
		}
		pdf_closexref(src);
		src = nil;
	}

	srcname = nil;
}

void opensrc(char *filename, char *password, int loadpages)
{
	fz_error *error;
	fz_obj *obj;

	closesrc();

	srcname = filename;

	error = pdf_newxref(&src);
	if (error)
		die(error);

	error = pdf_loadxref(src, filename);
	if (error)
	{
		fz_printerror(error);
		fz_droperror(error);
		fz_warn("trying to repair");
		error = pdf_repairxref(src, filename);
		if (error)
			die(error);
	}

	error = pdf_decryptxref(src);
	if (error)
		die(error);

	if (src->crypt)
	{
		int okay = pdf_setpassword(src->crypt, password);
		if (!okay)
			die(fz_throw("invalid password"));
	}

	if (loadpages)
	{
		error = pdf_loadpagetree(&srcpages, src);
		if (error)
			die(error);
	}

	/* TODO: move into mupdf lib, see pdfapp_open in pdfapp.c */
	obj = fz_dictgets(src->trailer, "Root");
	if (!obj)
		die(error);

	error = pdf_loadindirect(&src->root, src, obj);
	if (error)
		die(error);

	obj = fz_dictgets(src->trailer, "Info");
	if (obj)
	{
		error = pdf_loadindirect(&src->info, src, obj);
		if (error)
			die(error);
	}

	error = pdf_loadnametrees(src);
	if (error)
		die(error);

	error = pdf_loadoutline(&srcoutline, src);
	if (error)
		die(error);
}

void preloadobjstms(void)
{
	fz_error *error;
	fz_obj *obj;
	int i;

	for (i = 0; i < src->len; i++)
	{
		if (src->table[i].type == 'o')
		{
			error = pdf_loadobject(&obj, src, i, 0);
			if (error) die(error);
			fz_dropobj(obj);
		}
	}
}

/* --------------------------------------------------------------------- */

/*
 * Debug print parts of the PDF.
 */

int showbinary = 0;
int showdecode = 0;
int showcolumn;

void showusage(void)
{
	fprintf(stderr, "usage: mupdftool show [-bd] <file> [xref] [trailer] [object numbers]\n");
	fprintf(stderr, "  -b  \tprint streams as raw binary data\n");
	fprintf(stderr, "  -d  \tdecode streams\n");
	exit(1);
}

void showtrailer(void)
{
	if (!src)
		die(fz_throw("no file specified"));
	printf("trailer\n");
	fz_debugobj(src->trailer);
	printf("\n");
}

void showxref(void)
{
	if (!src)
		die(fz_throw("no file specified"));
	pdf_debugxref(src);
	printf("\n");
}

void showsafe(unsigned char *buf, int n)
{
	int i;
	for (i = 0; i < n; i++) {
		if (buf[i] == '\r' || buf[i] == '\n') {
			putchar('\n');
			showcolumn = 0;
		}
		else if (buf[i] < 32 || buf[i] > 126) {
			putchar('.');
			showcolumn ++;
		}
		else {
			putchar(buf[i]);
			showcolumn ++;
		}
		if (showcolumn == 79) {
			putchar('\n');
			showcolumn = 0;
		}
	}
}

void showstream(int num, int gen)
{
	fz_error *error;
	fz_stream *stm;
	unsigned char buf[2048];
	int n;

	showcolumn = 0;

	if (showdecode)
		error = pdf_openstream(&stm, src, num, gen);
	else
		error = pdf_openrawstream(&stm, src, num, gen);
	if (error)
		die(error);

	while (1)
	{
		error = fz_read(&n, stm, buf, sizeof buf);
		if (error)
			die(error);
		if (n == 0)
			break;
		if (showbinary)
			fwrite(buf, 1, n, stdout);
		else
			showsafe(buf, n);
	}

	fz_dropstream(stm);
}

void showobject(int num, int gen)
{
	fz_error *error;
	fz_obj *obj;

	if (!src)
		die(fz_throw("no file specified"));

	error = pdf_loadobject(&obj, src, num, gen);
	if (error)
		die(error);

	printf("%d %d obj\n", num, gen);
	fz_debugobj(obj);

	if (pdf_isstream(src, num, gen))
	{
		printf("stream\n");
		showstream(num, gen);
		printf("endstream\n");
	}

	printf("endobj\n\n");

	fz_dropobj(obj);
}

void
showmain(int argc, char **argv)
{
	int c;

	while ((c = getopt(argc, argv, "bd")) != -1)
	{
		switch (c)
		{
		case 'b': showbinary ++; break;
		case 'd': showdecode ++; break;
		default:
			  showusage();
			  break;
		}
	}

	if (optind == argc)
		showusage();

	opensrc(argv[optind++], "", 0);

	if (optind == argc)
		showtrailer();

	while (optind < argc)
	{
		if (!strcmp(argv[optind], "trailer"))
			showtrailer();
		else if (!strcmp(argv[optind], "xref"))
			showxref();
		else
			showobject(atoi(argv[optind]), 0);
		optind++;
	}
}

/* --------------------------------------------------------------------- */

/*
 * Clean tool.
 * Rewrite PDF.
 * Garbage collect.
 * Decompress streams.
 * Encrypt or decrypt.
 */

void
cleanusage(void)
{
	fprintf(stderr,
			"usage: mupdftool clean [options] input.pdf [outfile.pdf]\n"
			"  -d -\tpassword for decryption\n"
			"  -g  \tgarbage collect unused objects\n"
			"  -x  \texpand compressed streams\n"
			"  -e  \tencrypt output\n"
			"    -u -\tset user password for encryption\n"
			"    -o -\tset owner password\n"
			"    -p -\tset permissions (combine letters 'pmca')\n"
			"    -n -\tkey length in bits: 40 <= n <= 128\n");
	exit(1);
}

void
cleanexpand(void)
{
	fz_error *error;
	fz_obj *stmobj;
	fz_buffer *buf;
	fz_obj *stmlen;
	int i, gen;

	for (i = 0; i < src->len; i++)
	{
		if (src->table[i].type == 'n')
		{
			gen = src->table[i].gen;

			if (pdf_isstream(src, i, gen))
			{
				error = pdf_loadobject(&stmobj, src, i, gen);
				if (error) die(error);

				error = pdf_loadstream(&buf, src, i, gen);
				if (error) die(error);

				fz_dictdels(stmobj, "Filter");
				fz_dictdels(stmobj, "DecodeParms");

				error = fz_newint(&stmlen, buf->wp - buf->rp);
				if (error) die(error);
				error = fz_dictputs(stmobj, "Length", stmlen);
				if (error) die(error);
				fz_dropobj(stmlen);

				pdf_updateobject(src, i, gen, stmobj);
				pdf_updatestream(src, i, gen, buf);

				fz_dropobj(stmobj);
			}
		}
	}
}

void
cleanmain(int argc, char **argv)
{
	int doencrypt = 0;
	int dogarbage = 0;
	int doexpand = 0;
	pdf_crypt *encrypt = nil;
	char *infile;
	char *outfile = "out.pdf";
	char *userpw = "";
	char *ownerpw = "";
	unsigned perms = 0xfffff0c0;	/* nothing allowed */
	int keylen = 40;
	char *password = "";
	fz_error *error;
	int c;

	while ((c = getopt(argc, argv, "d:egn:o:p:u:x")) != -1)
	{
		switch (c)
		{
		case 'p':
			/* see TABLE 3.15 User access permissions */
			perms = 0xfffff0c0;
			if (strchr(optarg, 'p')) /* print */
				perms |= (1 << 2) | (1 << 11);
			if (strchr(optarg, 'm')) /* modify */
				perms |= (1 << 3) | (1 << 10);
			if (strchr(optarg, 'c')) /* copy */
				perms |= (1 << 4) | (1 << 9);
			if (strchr(optarg, 'a')) /* annotate / forms */
				perms |= (1 << 5) | (1 << 8);
			break;
		case 'd': password = optarg; break;
		case 'e': doencrypt ++; break;
		case 'g': dogarbage ++; break;
		case 'n': keylen = atoi(optarg); break;
		case 'o': ownerpw = optarg; break;
		case 'u': userpw = optarg; break;
		case 'x': doexpand ++; break;
		default: cleanusage(); break;
		}
	}

	if (argc - optind < 1)
		cleanusage();

	infile = argv[optind++];
	if (argc - optind > 0)
		outfile = argv[optind++];

	opensrc(infile, password, 0);

	if (doencrypt)
	{
		fz_obj *id = fz_dictgets(src->trailer, "ID");
		if (!id)
		{
			error = fz_packobj(&id, "[(ABCDEFGHIJKLMNOP)(ABCDEFGHIJKLMNOP)]");
			if (error)
				die(error);
		}
		else
			fz_keepobj(id);

		error = pdf_newencrypt(&encrypt, userpw, ownerpw, perms, keylen, id);
		if (error)
			die(error);

		fz_dropobj(id);
	}

	if (doexpand)
		cleanexpand();

	if (dogarbage)
	{
		preloadobjstms();
		pdf_garbagecollect(src);
	}

	error = pdf_savexref(src, outfile, encrypt);
	if (error)
		die(error);

	if (encrypt)
		pdf_dropcrypt(encrypt);

	pdf_closexref(src);
}


/* --------------------------------------------------------------------- */

/*
 * Draw pages to PPM bitmaps.
 */

enum { DRAWPNM, DRAWTXT, DRAWXML };

struct benchmark
{
    int pages;
    long min;
    int minpage;
    long avg;
    long max;
    int maxpage;
};

int drawmode = DRAWPNM;
char *drawpattern = nil;
pdf_page *drawpage = nil;
float drawzoom = 1.0;
int drawrotate = 0;
int drawbands = 1;
int drawcount = 0;
int benchmark = 0;

void
drawusage(void)
{
	fprintf(stderr,
			"usage: mupdftool draw [options] [file.pdf pages ... ]\n"
			"  -b -\tdraw page in N bands\n"
			"  -d -\tpassword for decryption\n"
			"  -o -\tpattern (%%d for page number) for output file\n"
			"  -r -\tresolution in dpi\n"
			"  -t  \tutf-8 text output instead of graphics\n"
			"  -x  \txml dump of display tree\n"
			"  -m  \tprint benchmark results\n"
			"  example:\n"
			"    mupdftool draw -o out%%03d.pnm a.pdf 1-3,5,9-\n");
	exit(1);
}

void
gettime(long *time_)
{
    struct timeval tv;

    if (gettimeofday(&tv, NULL) < 0)
	    abort();

    *time_ = tv.tv_sec * 1000000 + tv.tv_usec;
}

void
drawloadpage(int pagenum, struct benchmark *loadtimes)
{
	fz_error *error;
	fz_obj *pageobj;
	long start;
	long end;
	long elapsed;

	char *basename;

	basename = strrchr(srcname, '/');
	if (!basename)
	    basename = srcname;
	else
	    basename ++;

	fprintf(stderr, "draw %s:%03d ", basename, pagenum);
	if (benchmark && loadtimes)
	{
		fflush(stderr);
		gettime(&start);
	}

	pageobj = pdf_getpageobject(srcpages, pagenum - 1);
	error = pdf_loadpage(&drawpage, src, pageobj);
	if (error)
		die(error);

	if (benchmark && loadtimes)
	{
	    gettime(&end);
	    elapsed = end - start;

	    if (elapsed < loadtimes->min)
	    {
		loadtimes->min = elapsed;
		loadtimes->minpage = pagenum;
	    }
	    if (elapsed > loadtimes->max)
	    {
		loadtimes->max = elapsed;
		loadtimes->maxpage = pagenum;
	    }
	    loadtimes->avg += elapsed;
	    loadtimes->pages++;
	}

	if (benchmark)
		fflush(stderr);
}

void
drawfreepage(void)
{
	pdf_droppage(drawpage);
	drawpage = nil;

	/* Flush resources between pages.
	 * TODO: should check memory usage before deciding to do this.
	 */
	if (src && src->store)
	{
		fflush(stderr);
		/* pdf_debugstore(src->store); */
		pdf_emptystore(src->store);
	}
}

void
drawpnm(int pagenum, struct benchmark *loadtimes, struct benchmark *drawtimes)
{
	fz_error *error;
	fz_matrix ctm;
	fz_irect bbox;
	fz_pixmap *pix;
	char name[256];
	char pnmhdr[256];
	int i, x, y, w, h, b, bh;
	int fd = -1;
	long start;
	long end;
	long elapsed;

	fz_md5 digest;